interesting topic, I would probably a regular trainer aspiring to be the champion and competing in the league. The team has undergo some changes from the time I only able to play up to fifth gen. here are they now
these guys would be in my team, now for nickname and reason
Soundwave (Noivern): Noivern is now sharing with Flygon as my favorite pokemon of all time, but for this team, I pick Noivern as the ace sorry Flygon I still like you no matter what , a speedy sound based attack dragon bat is just one hell of an awesome idea. He'll be the ace of my team and probably my main use of transportation.
Hozuki (Greninja): The ninja frog catch my attention through his design and his hidden ability. He'll be my starter pokemon. He'll help me in water transportation.
Inferno (Infernape): Infernape is probably the only pokemon in this team that survive the numerous change in my favorites/team that I would want to have in real life, which just show how much I love this flaming monkey. He'll be the team main brawler
Arrow (Decidueye): The arcer, the owl, the awesome. I never really like grass type, and up until gen 6 the only grass type I like was Leavanny and Torterra. Gen 7 arrived and give me this, Archery are pretty interesting, and have wide movepool to make himself almost as confusing as Infernape
Bugger (Vikavolt): Now electricity is important, and fortunately, Vikavolt is an electric type pokemon, he's not the toughest around or the fastest, but I know that he'll be one hell of a pokemon to have in the team
Metallo (Metagross): Now while Noivern (or Flygon depending on the situation) is the ace of my team, Metagross is going to be the team main powerhouse, and the main megamon of the team since sadly my ace is incapable to mega evolve
honorary mention:
Draggy (Flygon): before gen 6 arrive, Flygon was the ace of my "team that I would want to have in real life" but Noivern took that spot from him. Personally, if in real life I find Flygon first, then I am definitely going to add him to the team, making him the ace
Strongarm (Swampert): same with Flygon, Swampert is without a doubt my most favorite water type pokemon, but now he kinda share that spot with Greninja though I would probably prefer Greninja now
Blade (Leavanny): Leavanny manage to impress me when I was playing BW the guy is a powerhouse in my team lol and whenever I'm lacking a grass type and Leavanny is available, he'll be the go to pokemon of mine
These honorary mention will replace either of the three pokemon: Noivern, Greninja, Decidueye respectively if if either one of the three is unavailable due to some circumstances