mmm.. tricky I didn't play the game I just watched the video and looked carefully at the screen caps.
I'm going to offer my honest feelings- they are just mine and I am a single person on the internet so take with a grain of salt if you like.
The game visually doesn't appeal to me.. game play is okay but the "samoan splash" image or the menu with all the wrestlers in it...no. The wrestlers pixel profile pictures look amazing!-fine pixel artwork right there! but the purple maroon background doesn't suit well possibly- it needs something- writing... excitement... I don't like the dark background. It's too heavy on the mood. Wrestling is exciting right?
When battling do you get a sprite of the wrestler? or just the picture of them in a frame fighting? In pokemon you kinda got to see the pokemon battling even if it was just their sprite and some effects over the top. Don't judge me but I have only seen WWE and I'm not a huge westling fan- but wrestling usually has a lot of action. I feel 2 picture frames attacking each other means it's completely lacking headlocks or grabs or whatever they do we love to watch lol Not saying you have to animate all that-but you could jiggle a sprite around when it gets hit or show a "solarbeam" attack pokemon. You could also use a streetfighter battling system rather than pokemon but keep the pokemon catching mechanic... that would actually be super cool and totally unique from pokemon. Catch a wrestler and have them streetfighter battle it out and level them up-one hit punch weaklings for exp. to gain those levels and fight at the end and beat the elite 5...Damn that is something different I would honestly love to play haha. Make something new-if I wanted to play pokemon I would just play pokemon without the wrestlers because I don't like wrestling- again one dumb girl on the Internets opinion.
I think if you added story and a heap of wrestling facts or hidden knowledge into your game plus more action that would be cool! I suggest looking at wrestling matches or games and try and copy the way they show you the players profiles/stats etc. I am sure they do so in a way that invites the viewer to feel excited or feel anticipation. From memory its lots of flashing animation and fire/sound effects lol- but it's more than this, just my memory.
By keeping it "wrestler fan niche" without making anything gameplay wise new, you are really narrowing your audience. So I think you have 2 paths, make a wrestler fan super super happy with fun pokemon like game-play, insider wrestler knowledge/facts and all the wrestler action feels-make it actually feel like watching wrestling! or make something new that will appeal to everyone that has wrestlers.
You made a functioning game- that's a huge success and not a failure at all! I haven't done that yet!!!! You feel like you wanna keep going don't stop! I think you should make a game because you want to and you really enjoy it, not worry about if people buy it or not. If you are passionate about this game I suggest keep polishing it up and looking critically at it and I think you could make it amazing! You will learn if so much too if you try and test new things in your game- or start with a fresh slate and brand new idea- up to you. Either way it’s NOT a failure.
Hope this helped! I wanted to give my honest opinion and be as constructive as possible :) I love your game. I can tell you put a lot of effort into it!
edit: did you add some female wrestlers or are they all dudes? That could also be limiting your audiences appeal. Random, but I remembered a wrestler I really loved who was on terrace house named Hana Kimura. She appealed to women as a strong female and men because gotta be honest she was a real hottie.