Past attempts to cross Pokémon with GTA V have produced material that would probably send Cthulhu to a therapist and yet the community does not waver.
What very well may be the most influential Japanese video game franchise in the history of the industry, Pokémon has an innumerably large fanbase Pokemon Go sees more users and engagement on mobile than Facebook!). Despite what the "official" target audience may be, we all know that the biggest consumers of Pokémon titles are adult gamers, though obviously there are young fans too.
If you've ever played GTA V, then you'll know that despite being rated 18+, there are plenty of children playing the game. As such, the audiences of both franchises greatly overlap. This makes the fact that there hasn't been a boatload of crossover fan content produced damn surprising. However it is possible that people were simply discouraged by Merfish's abomination linked to above.
Regardless, one brave soul took it upon themselves to add a fully functional Pokéball mechanic to GTA V, allowing players to toss the red/white spheres at any NPC. Like in the original, the victim must have been weakened beforehand, and the required amount of damage varies from the rank of the NPC. If you're successful in capturing them, then you can "choose" the given NPC, toss their ball, and the poor sod will now be fighting on your side.
The mod isn't in a finished state, however the author has said that he does not plan to continue working on it. Regardless, this file has gotten quite popular, and many comments beg InfamousSabre to continue refining it.
