Canon provides lots of examples of Sunset Shimmer doing cool things and this gives fanfic writers license to have her display an awesome array of capabilities. But how capable is Sunset Shimmer in canon? What capabilities can fanfic writers use as an extension of canon and what do they have to create out of whole cloth? 

I’m looking for canon references in the EQG movies, videos, and in the 2 main comics, The Fall of Sunset Shimmer and Equestria Girls Holiday Special with Anon-a-Miss. I know there are other comics, video games, etc., but I feel these are the most widely accepted examples of Sunset’s character. Are there others that should be considered as well?

I’ll start. Here are come categories with canon examples of Sunset’s capabilities. What other canon examples do you have of Sunset’s capabilities that fanfic writers can expand off from?

Magical

• Sunset was Celestia’s personal student, showed power greater than any other student in her SGU exam, and saw herself as an Alicorn in the magic mirror in The Fall of Sunset Shimmer.
• Sunset was overpowered as both Demon Sunset in Equestria Girls and Daydream Shimmer in Friendship Games. 

Intelligence

• Sunset represents CHS in the math challenge in the Equestria Games, so is likely considered the smartest student in the school at the time (though she loses to Sci-Twi).
• In Finals Countdown, Sunset isn’t worried about the final test and doesn’t study very hard. She gets an A+ like Sci-Twi. Sunset beats Sci-Twi at Chess. 

Art

• Sunset draws a comic with the Mane 7 as superheroes in Super Squad Goals.
• Sunset is secretly the street artist “Flanksy” and shows she is as good or better than Rarity at art when she makes the window displays in Display of Affection.

Music

• Sunset and Twilight both sing lead in the Rainbow Rocks finale, so they may be equally good as singers. Any other examples that would show one above the other?
• Rainbow Dash plays lead guitar before Sunset joins the Rainbooms as a guitarist. Is there any canon evidence that Sunset is Dash’s equal or superior on the guitar?

Video Games

• Sunset plays video games and streams, so she is likely good at them (even though she loses to Fluttershy in Game Stream). AJ and RD play video games in Rainbow Rocks (AJ is winning). Do we have any examples of Sunset beating AJ or RD at video games?

Physical Capabilities

• Is Sunset ever compared in physical capabilities to Rainbow Dash (not counting RD’s super speed) or Applejack (not counting AJ’s super strength)?

Fighting

• Any examples of Sunset's fighting ability either physically or magically (other than overpowering someone with magic along with all the girls combined?) 
• There isn’t a lot of fighting in EQG, but in MLP we have examples of Rainbow Dash, Applejack, and Rarity fighting physically and Twilight shooting beams and making shields. Does Sunset have examples like that?

I look forward to seeing what other canon examples of Sunset’s capabilities that come to mind!

re: Physical Capabilities/Fighting

Sunset is part of the fencing team.

In Sunset Shimmer's Time To Shine not only is she shown capable of easily memorizing chemistry formulas thanks to years of learning magical formulas and spells, but she also seems to possess some level of programming ability since she designs an app to help with the events of the book.

Sunset is good at a lot of things in the Canon, is there any skills where she fails to be good at?

Sunset makes food at a Sushi place, so she’s decent at cooking as well.

7412673
Great catch and makes perfect sense for Sunset.

Do you remember which episode that is shown in? Is it the one where AJ and RD join school clubs?

7412747 Yep. the one where AJ and RD do that. AJ shows up in the fencing club holding an actual fence

7412752
Queen of Clubs.

7412658
One big overlook here is her geode powers under Magical.

• Sunset can read the thoughts and memories of people and to at least some degree objects. Ordinarily this requires direct physical contact and takes the form of visions, but when the geodes are supercharged, she can hear the surface thoughts of everyone in her immediate vicinity - although the "noise" thus created is an impediment to both picking out more detail and any other task. She has this power when anywhere within the general vicinity (a mile or two) of her functioning geode, even if she isn't wearing it.
• She can also use the geode to "Super Pony Up", activating her demipony form at will while also donning a unique and stylish outfit. (What happens to her existing clothes at this time is unclear.) The precise form of said outfit has changed at least once. This ability requires her to touch her geode to activate, and may cancel if she is not wearing it (depending how literally you take that Flash short).

7412794
So let’s talk about Sunset’s geode / superpowers.

It seems that when in superhero-mode all the girls get flight, and a bit of enhanced durability and strength. In Cheer Her On they all got blown through a wall and stood right up. Fluttershy easily carried Microchips while flying, something that I doubt she could do in normal form (though pony Fluttershy can wrestle bears!).

You described Sunset’s empathy powers well.

In Cheer Her On, Sunset is also the focus for all the girl’s powers and shoots a rainbow laser that defeats the giant robot. This seemed like a lesser version of Sunset being the focus of the girl’s powers when she transformed into Daydream Simmer to defeat Midnight Sparkle in Friendship Games. All the points to Sunset being the only one that can act as a focus. In another example, the Rainbooms at the end of Rainbow Rocks couldn't combine their powers until Sunset added her voice to the band.

Has Sunset exhibited any other super powers in canon?

7412726
I agree that understanding the flip side of this argument is also useful when writing Sunset Shimmer. Some things she has problems with include:

Sunset's main issue is anger. She gets frustrated and can lose it when she can’t solve a problem or fix things she thinks are her fault or unfair. See: 
- Forgotten Friendship
- Sunset's Backstage Pass
- First 3 movies
- Rollercoaster of Friendship
- Shorts: Overpowered, Game Stream

Sunset’s anger can lead to her jumping to conclusions about people who she decides have “wronged” her, even if they may be innocent. Note how she wrongly accused Trixie in Forgotten Friendship and Adagio and The Dazzlings in Sunset’s Backstage Pass.

Sunset doubts her own reformation. This was reflected in her reticence to see Celestia. For both see Forgotten Friendship as well as how she sees her demon form in a reflection during My Past Is Not Today.

Sunset is not a morning person, see Monday Blues.

These are mostly character flaws, not skills that Sunset is demonstrated to do badly in canon.

What are some things that someone else in the Mane 7 has been clearly established as doing better than Sunset?

7412895

I am talking about skills she is not good at, not flaws in her personality.

7412867
Except that in Rollercoaster of Friendship, everyone channelled their power to Rarity.

7412966
You're right, I had forgotten. That suggests that any of the 7 can act as the focus.

Rarity's "focus bolt" was different than Sunset's as well, more like white lightning than a rainbow laser.

Suggests that each girl may express their "focus bolt" in their own way.

7412955
I couldn't think of many (any?) things we saw Sunset do poorly. That was why I was looking for things that the other girls did better than Sunset as a sideways way to look for answers to the question.

However, I can't think of any canon evidence that Sunset is an extraordinary athlete or combatant, while we do have evidence that RD is an extraordinary athlete even without super powers.

Anyone have suggestions for things Sunset is not at least "good" at?

The comic Canterlot High: March Radness shows that Sunset is the one of the seven who doesn't managed to beat Rainbow Dash at a specific sport. And she's really not good at football tactics: she says at one point "My skills are in music and academics. I still can't wrap my head around all the soccer strategy and field positions. It is just too much!" Then she makes a suggested strategy which is so bad Rainbow Dash can't help but step in to sort it out.

In the school play series of shorts, she's generally a pretty capable (assistant) director, but possibly not a great actress: her improvised monologue in her Opening Night ending is very stilted and awkward, even if she manages to pull it together at the end.

And, um, she's not very good at walking while dressed as a carrot, in Holidays Unwrapped.

One demonstration of her being awesome that I don't think has been mentioned above: in Forgotten Friendship, she works out that Wallflower has the Memory Stone, and is probably about to use it on her; so she starts the camera recording and leaves a note for herself in her pocket. That definitely shows some canny planning skills that are a bit different to just academic "intelligence".

7413001
The Rainbow Dash ending in Stressed in Show indicates she's definitely not as good at jogging as Rainbow Dash and may be even worse than Sci-Twi at it. Little weird given other shorts and movies show she is at least capable of keeping up with the rest of the Rainbooms physically (sure Rainbow Dash and Applejack are the most physically fit, but I'd say Sunset's closer with Rarity, Fluttershy, and Pinkie in physical skill) and the Queen of Clubs short shows she is good in fencing which requires some physical skill.