What is Detective Pikachu's Secret Identity? (Pokemon Detective Pikachu Movie)

The Detective Pikachu movie is shaping up to be a CRAZY time! Seriously, a talking Pikachu with a mysterious past in a movie full of live action Pokemon? This was begging for a theory. Today, I found out what I think will be the BIGGEST twist in the entire movie! No, I'm not talking about MewTwo. I mean, they even showed him in the trailer. No, I'm talking about who Detective Pikachu's forgotten trainer really is! Grab your pokedex Theorists!