Problem:
Have an idea for a story, yet I don't know if its considered a true 'crossover' or not.

Background:
It's from one of my favorite stories, however I'm not using the true characters names what-so-ever. Also, I'm only using the ideas from the first few chapters. The rest will be made up on my own. Secondly, the characters will be OCs and will not be referred to their true names. The characters will still have their personalities like the ones mentioned in the book.
I don't know if this still counts as a true crossover, but if it does then GREAT.
Oh and I can't tell you the book I'm referring to, otherwise my idea will be stolen

Thanks for everything and if you want a spot in the story, your character's name must fit the qualities stated below:
1st OC: Pony is too difficult for the parents to control, he however can control his own self without issue. [More of a leader figure than a follower.]
2nd OC: Ward of the State (Meaning RICH PONY, not a 'snooty' one), however; the pony isn't talented enough to be kept alive (pianist).
3rd OC: Misguided Pony; considered to be a terrorist [clapper]; susceptible to anypony.
ALL OF THESE HAVE TO BE COLTS WILL ASK FOR FILLIES LATER ON.

Thanks for the help.

White Out
Earth Pony -

Known to some as 'TB' shorthanded for a more embarrassing name, Tibbles. Was his nickname, and now it stuck. Wears a blue Christmas hat everywhere, as well as a monocle he keeps for sentimental reasons.

Mane - Silver
Coat - Bleach-white
Eyes - Storm gray.
Cutie-mark - Whatever you need it to be in your story

Can be fitted into any of those slots. If you need a reference, just make a ponified version of my avatar.

Can be any of your

I could make a colt version of some of my OCs.
For the 1st
Name: Climber
Breed: Earth Pony
Gender: Male
Colors: Coat - sandstone yellow; Mane + Tail - pale ice blue, ruffled and cropped short.
Cutie Mark: A red, zigzagged arrow travelling up a mountain.
Character: Strong-willed, individualistic, likes to strike out on his own, gets very bored when he has no challenge and tends to travel into the wilderness to find one (got his Cutiemark when he climbed a mountain).

For the 3rd
Name: "Power Focus" (original name abandoned)
Breed: Unicorn
Gender: Male
Colors: Coat - Lavender, Mane + Tail - deep green, like algae
Character: As a result of bullying, he is obsessed with power, more precisely the power to take revenge and "Show them all!" - after setting one of the bullies on fire a few years later, he was barred from studying magic due to his criminal record. He disappeared into the wilderness for years, trying to teach himself magic - not looking at spellwork, simply by going after intuition and what caused the animals he caught the most painful deaths. He eventually, by pure chance, found the cottage and legacy of a long deceased exiled unicorn - a book about black magic, containing knowledge suppressed for over two hundred years. When he returned to society, his cutie mark was one of the symbols from the exile's book.