SkunkyArt | Akrononym — What if Usopp was a Pokemon Trainer

Forretress: a reference to Usopp's Bagworm Star, with which he defeated Sugar, as well as his love for all kinds of bugs. Attacks like Stealth Rocks and Seed Bombs reflect his tricky, long-distance fighting style, while Payback can be seen as a hint towards the Impact Dial
Attacks: Seed Bombs - Stealth Rocks - Explosion - Payback

Sudowoodo: it fools others into thinking that it's a tree, similar to how Usopp constantly lies about his true strength. Wood Hammer is a clear reference towards Usopp's infamous hammer skills while Foul Play is yet another hint towards his many tricks during combat
Attacks: Stone Edge - Wood Hammer - Tearful Look - Foul Play

Swiftry: just like Usopp, Swiftry has a long nose, uses plants during combat, and is generally known for its trickery. It's also a clear reference to Usopp's use of various plants during combat. Swagger is the clearest hint towards Usopp's constant liest that exists in Pokémon
Attacks: Seed Bombs - Fake Out - Swagger - Facade

Heracross: not the best representation of Usopp's growth into a warrior, but I think the fighting-type does kinda fit in the regard. Heracross might also very well be the best hint towards Usopp's love for bugs possible. Pin Missile is another reference towards Usopp's role as a sniper, which is also represented with the always-hitting Smart Strike
Attacks: Megahorn - Bulk Up - Pin Missile - Smart Strike

Ace Pokémon Inteleon: starting as cry babies who can't do much, both of them would grow into brave warriors who take out their opponents from afar. Snipe Shot... you can't get any more sniper than this!
Attacks: Snipe Shot - Hydro Cannon - U-turn - Air Slash