Sorry mate, can’t help much on this kid! All I know is that he was supposed to be a package deal with Kayky (who’s a tremendous talent) for City when they announced him a while ago, but there was a delay because Metinho’s parents are Congolese and there were issues with visas, etc. so I’m guessing that has been sorted out now, hence the announcement.
Metinho has barely played for the first team, so I haven’t seen much of him, unlike Kayky, but City have an extremely strong scouting presence in youth football in the Rio area, so it’s not surprising they’ve made this deal based on what they’ve seen at that level (Fluminense’s underage groups are a talent factory).