I am... a really bad pokemon fan and don't know what the different generations are I only started playing them on my 3DS and haven't played that many games so I'll just list the games I have played and what starters I chose, if that's okay!
Pokemon X: I picked Bulbasaur and Fennekin! I was super excited when I got to pick Bulbasaur too Bulbasaur is one of my favourite pokemon!
Pokemon Sun: I picked Popplio
Pokemon Shield: I picked... Sobble, I think! Although Grookey is really cute and I was definitely flipping between those two for a minute.
Gen 1: Charmander
Gen 2: Cyndaquil
Gen 3: Torchic
Gen 4: Chimchar
Gen 5: Can't remember
Gen 6: Froakie
Gen 7: Litten/Pikachu (in Let's Go Pokémon)
Gen 8: None (yet)
I've replayed them and gone with different starters but to the best of my memory these were first playthrough choices.
Gens 1 - 4: the water starters
Gen 5: Snivy
Gen 6: Froakie
Gen 7: Rowlet
Gen 8: Sobble
I think my mindset for a long time was that water starter = someone who could use surf which is a useful move in and out of battle. And I liked the final evolution designs more than the others each time. That might not apply to gen 1 however, I had no idea what the game would be like so I probably just found Squirtle the cutest.
Snivy was because of it being so smug and memeworthy. Froakie because the other finals that gen looked bad. Rowlet because it was cute and ghost/grass sounded cool. Sobble because inteleon reminds me of Gex. I remember Sobble vs Grookie being a tough choice.
Here's what I chose the first time I played each generation, followed by what wound up being my favorite later:
Gen I: Squirtle (Favorite: Charmander)
Gen II: Cyndaquil (Favorite: Chikorita)
Gen III: I actually skipped Gen III when it was new, I forget what I chose when I went back and played it years later, might have been Mudkip (Favorite: Grovyle)
Gen IV: Piplup (Favorite: Piplup)
Gen V: Oshawott (Favorite: Dewott)
Gen VI: Froakie (Favorite: I honestly don't really care much for any of the Gen VI starters, I suppose Greninja is kind of cool)
Gen VII: Popplio (Favorite: Decidueye)
Gen VIII: Sobble (Favorite: Inteleon)
Interestingly, I choose water type starters a lot when I play a generation for the first time, but I often wind up liking others better later on, whether because of their evolutions or their appearances in other games (Looking at you, Pokémon Mystery Dungeon). And I didn't realize how often I chose water types until I made this list. ^o^;>
I've played some games multiple times, so I'll list my favorites for those. For the two I've only played once (gens 2 and 7) I actually prefer a different starter now.
Gen 1: Bulbasaur (my all time favorite Pokémon)
Gen 2: Cyndaquil (but prefer Chikorota now)
Gen 3: Treecko
Gen 4: Piplup
Gen 5: Tepig
Gen 6: Fennekin
Gen 7: Popplio (but prefer Rowlet now)
Gen 8: Sobble (not really a fan of any of the starters for this region)
Looking back, I do have a preference for grass starters. That's kind of funny since otherwise, I usually don't use grass types very much. I've always considered myself a fire type lover, but as I've gotten older my tastes have changed. I still love using fire types, but am not a fan of the fire starters. None of my very favorite starters (Bulbasaur, Treecko, Piplup) are fire types.
listing my picks as what i used the very first time i played each gen & what starter is my favourite to pick now!
GEN 1: Charmander (favourite: Bulbasaur) GEN 2: Chikorita (favourite: Cyndaquil... and let's just say I've never actually beaten a game with my first pick of Chikorita, it's very hard to use especially as a kid) GEN 3: Torchic (favourite: Mudkip) GEN 4:Piplup (favourite: Chimchar solely b/c of Sinnoh's lack of fire types...) GEN 5:Oshawott (favourite: Tepig) GEN 6: Froakie (do not have a favourite. sorry Kalos starters) GEN 7: Popplio (favourite: still Popplio <3) GEN 8:Scorbunny (also don't really have a favourite i don't really like any of the final gen8 evos so)
in the end it's a pretty even split between using and preferring water & fire starters lol. sorry to grass starters -- i still like a lot of them, they're just not my preferred choice
I had to specifiy which games within the gens since FireRed is technically gen 3 I think and Diamond and Heartgold are both gen 4!
Gen 3: FireRed: Squirtle
Gen 4: Diamond: Piplup
Gen 4: Heartgold: Cyndaquil
Gen 5: Black/Black 2: Oshawott
Gen 6: X: Froakie
Gen 7: Moon/Ultra Moon: Popplio
Gen 8: Shield: Sobble
still dont know why I went with cyndaquil in heartgold since I always do the water starter lmao
Gen 1: Charmander (I prefer Squirtle but like Charizard over Blastoise)
Gen 2: Cyndaquil (I do love Totodile as well but fire types are just harder to get)
Gen 3: Mudkip
Gen 4: Chimchar
Gen 5: Oshawott
Gen 6: Froakie
Gen 7: Rowlet
Gen 8: Scorbunny
1: Squirtle
2: Cyndaquil, just cause I love Quilava
3: Mudkip
4: Piplup (Gen 4 has the starters where’d I’d happily pick any of them though)
5: Oshawott (Love Dewott)
6: Chespin (My favourite ever starter)
7: Don’t really care, probably Rowlett
8: Again don’t care, hate Cinderace. Rillabooms stupid vine hair annoys me and Inteleon is decent. Would probably pick Grookey