Yes, my first choice is a Pokemon trainer, however and I know it's probably cliche but I would want to be a Pokemon Coordinator. you can show off your Pokemon and battle too (and I love battling). and let me tell you the number of combinations you can do plus the work you have to put into getting your required result for the performance, is one of the best parts of the career.
[Man, I hope they bring back contests in Sun & Moon. ]
I'd probably just stick with being a trainer. Common answer yes, but I think it would be fun to train different types of Pokemon especially normal types. But if you want a different answer then maybe I'd work at a Pokemon daycare center and take care of and play with the Pokemon trainers drop off until they come back.
Probably an E4 member but that is very modest of me , I'd love to be a general trainer who knows a lot about breeding as well, and I'd eventually love to run my own gym, and one day be an E4 member to put it more clearly.
Pokemon Trainer, although I would give Contests, breeding, science or even journalism a try.
The Pokemon world feels like a place where you can more easily pursue several different careers at once and stick with what seems to suit you better in the end.