*Victory Fanfare*

Mane 6

• Twilight -- Stands on her rear hooves and does an awkward dance.
• Rainbow Dash -- Does a somersault in the air and strikes an awesome pose.
• Fluttershy -- Wipes her forehead and sighs in relief.
• Rarity -- Stands tall and bows her head.
• Applejack -- Tosses her hat which lands back on her head and crosses her hoof.
• Pinkie Pie -- Balloons come from nowhere as Pinkie jumps up and down repeatedly.

Others

• Spike -- Pumps his fists and puffs out his chest.
• Princess Celestia -- Closes her wings and her eyes while bowing regally.
• Princess Luna -- Closes her wings but keeps her eyes open and raises a hoof as she bows.
• Princess Cadence -- Raises her head up high and places her hoof on her heart.
• Shining Armor -- Salutes and bows.
• Sunset Shimmer -- Jumps in the air with a smile on her face and puts her hands/hooves on her hips.
• Trixie -- Stands on her rear hooves and displays fireworks.
• Starlight Glimmer -- Smiles and claps her hooves.

Young/Student 6

• Sandbar -- Laughs and jumps in the air once.
• Smolder -- Crosses her arms and winks.
• Gallus -- Flashes a peace sign.
• Ocellus -- Rubs her hoof in a shy manner while smiling.
• Yona -- Stomps the ground in a cheerful manner.
• Silverstream -- Spins around and holds her face with an excited grin.

Great so far! I can imagine a few of these are based off existing poses done by these characters before, but I couldn't discern which is which. I do see familiarity with Trixie's pose for example.