They're all performing some kind of attack, which I think is kinda neat.

i can't believe i actually did all of them

Bulbasaur - Leech Seed.
Ivysaur - Razor Leaf.
Venusaur - Vine Whip.
Charmander - Ember.
Charmeleon - Slash.
Charizard - Hard to say. It's a small fireball. Either Flamethrower or Fire Spin (or maybe just Ember again).
Squirtle - Withdraw.
Wartortle - Skull Bash.
Blastoise - Hydro Pump.
Caterpie - String Shot.
Metapod - Harden.
Butterfree - Either Stun Spore, Poison Powder, or Sleep Powder. Hell, maybe Whirlwind.
Weedle - Poison Sting.
Kakuna - Harden.
Beedrill - Fury Attack, or Twineedle.
Pidgey - Sand Attack.
Pidgeotto - Wing Attack.
Pidgeot - Quick Attack or Agility.
Rattata - Focus Energy.
Raticate - Bite, Hyper Fang, or Super Fang.
Spearow - Peck.
Fearow - Drill Peck.
Ekans - Leer, or maybe Glare.
Arbok - Acid.
Pikachu - Thundershock or Thunder Bolt.
Raichu - No idea. Maybe Thunder Wave?
Sandshrew - Sand Attack.
Sandslash - Pin Missile.
Nidoran F - Growl.
Nidorina - Bite.
Nidoqueen - Um. Roar? I don't actually think she's doing anything.
Nidoran M - Tackle or Horn Attack or Fury Attack?
Nirodino - Focus Energy.
Nidoking - Horn Drill.
Clefairy - Double Slap.
Clefable - Metronome.
Vulpix - Tail Whip.
Ninetales - Growl or Roar again? Maybe it's nothing again.
Jigglypuff - Sing.
Wigglytuff - Disable.
Zubat - Supersonic.
Golbat - Wing Attack.
Oddish - No clue. Maybe Absorb or something, or some kind of Powder move.
Gloom - Looks like Solar Beam to me.
Vileplume - Petal Dance.
Paras - Leech Life.
Parasect - Spore.
Venonat - I don't know. Maybe Absorb again, or a Powder move.
Venomoth - Supersonic, or maybe Hypnosis, if it could learn that.
Diglett - Dig.
Dugtrio - Earthquake.
Meowth - Pay Day.
Persian - Slash.
Psyduck - Scratch or Slash.
Golduck - Scratch or Slash.
Mankey - Karate Chop.
Primeape - Fury Swipes, or Thrash.
Growlithe - No clue. Doesn't look like Ember to me, but it might be.
Arcanine - Growl.
Poliwag - Hypnosis.
Poliwhirl - Water Gun.
Poliwrath - Double Slap.
Abra - Teleport.
Kadabra - Could be any damaging Psychic-type attack, really. Confusion, Psybeam, or Psychic.
Alakazam - Again, could be any of them, but it's probably Psychic. Could be Recover, too.
Machop - Low Kick.
Machoke - Seismic Toss.
Machamp - Submission.
Bellsprout - Wrap.
Weepinbell - Acid or Sludge.
Victreebel - Uh, Razor Leaf?
Tentacool - Supersonic.
Tentacruel - Constrict or Bind.
Geodude - I don't know. Maybe Rock Throw, or Tackle.
Graveler - Defense Curl.
Golem - Self-Destruct or Explosion.
Ponyta - Fire Spin, maybe.
Rapidash - Agility?
Slowpoke - ...It doesn't appear to be doing shit.
Slowbro - Amnesia.
Magnemite - Thunder Wave?
Magneton - Supersonic.
Farfetch'd - Swords Dance.
Doduo - Growl.
Dodrio - I don't know. Couldn't even really guess. MAYBE it's Rage.
Seel - Rest.
Dewgong - Aurora Beam or Ice Beam.
Grimer - Poison Gas.
Muk - Sludge.
Shellder - Supersonic.
Cloyster - Spike Cannon.
Gastly - Doesn't look like it's doing anything. Maybe Night Shade.
Haunter - Doesn't look like it's doing anything. Maybe Hypnosis.
Gengar - Dream Eater.
Onix - Maybe it's actually doing Bide, but I'm not sure.
Drowzee - Pound.
Hypno - Meditate.
Krabby - Vicegrip.
Kingler - Crabhammer.
Voltorb - Reflect or Light Screen.
Electrode - Self-Destruct or Explosion.
Exeggcute - No idea. Maybe Growth.
Exeggutor - Growth.
Hitmonchan - Comet Punch, or Mega Punch.
Lickitung - Slam, or Body Slam.
Koffing - Self-Destruct.
Weezing - Smog.
Rhyhorn - Maybe Rage.
Rhydon - Couldn't guess. Horn Attack?
Chansey - Sing.
Tangela - Wrap or Bind.
Kangaskhan - Dizzy Punch.
Horsea - Smokescreen.
Seadra - Water Gun.
Goldeen - Supersonic.
Seaking - Horn Drill.
Staryu - Swift.
Starmie - Water Gun.
Mr. Mime - Reflect.
Scyther - Swords Dance?
Jynx - Lovely Kiss.
Electabuzz - Thunder Punch.
Magmar - Flamethrower.
Pinsir - I have NO idea. Is that supposed to be Guillotine or something?
Tauros - Take Down, maybe.
Magikarp - Splash.
Gyarados - Dragon Rage.
Lapras - Nothing. Nothing that I can see, anyway.
Ditto - Transform.
Eevee - Tail Whip.
Vaporeon - Mist.
Jolteon - Pin Missile.
Flareon - Fire Spin.
Porygon - Sharpen, or maybe Tri Attack. Less likely Conversion.
Omanyte - Water Gun.
Omastar - Spike Cannon.
Kabuto - Harden.
Kabutops - Slash.
Aerodactyl - Wing Attack.
Snorlax - Headbutt? Or maybe Body Slam or Double-Edge.
Articuno - I dunno. Doesn't look like Ice Beam or anything.
Zapdos - I can't tell. Only its feet are glowing with electricity.
Moltres - Sky Attack, perhaps.
Dratini - Wrap or Bind.
Dragonair - Dragon Rage?
Dragonite - ...Is that supposed to be fucking Hyper Beam? Wow.
Mewtwo - ...Rocks. Ummmmm...
Mew - Metronome. You can see its wagging its finger.

Kakuna confirmed to have creepy little arms.