My only concern is Trincao and Ferran's ages both being 20. A club like Barcelona can't rely on so much youth (add Ansu to the mix).
Adama on the other had is a great profile when you just need someone to get the ball and tear the opponent apart in the last 20/30s of a match, at the right age. As Braithwaite is hinting, we really need some raw pace and power.
IQ wise though I do worry the club de amigos would get frustrated (again) at his playing style. Does not suit the "get the ball and give it to Messi at all costs" tactics.
Ferran is young but at the same time quite experienced already. He'll have around 100 games at the top level (La Liga, CL/EL, CDR) at the end of this season and he also has over 40 games for Spain youth teams.
As I've said many times I believe we should do a rebuild and all those young players should get enough minutes to prove their worth. Sure, for next season we can loan Trincao and keep Ferran, MB (I'd seriously consider keeping him if he'll play well for the rest of the season) and Fati as our wingers alongside Messi, Suarez and Griezmann. (I don't think we should spend 100m on Lautaro if we'll keep Suarez but we will so this probably means MB will be sold instead).
At this point I don't really care anymore if Messi and his amigos will get frustrated at young players making mistakes. They can seriously all just f*** off if they can't accept growing pains of youngsters in the team (and also for ignoring a certain player in the squad because they're mad we've signed him instead of bringing back their amigo). We should look to start building a post-Messi team and Messi should also accept that not every attack must go through him.
Also, I think Adama would be a much more frustrating player to play with for our seniors than Ferran. And as it was already mentioned he'd probably cost twice as much. So it's an easy choice for me.