Koopmeiners - been really good for Atalanta. Maybe unlikely to move on so quickly? He'd be a great backup option to FDJ stylistically though and probably my favourite semi-realistic choice. Atalanta are a selling club.
Guendouzi - been extremely impressive this season for Marseille. Take a look at his stats and he stands out across the board. Not sure about his attitude problems though, as that seemed to be the issue at Arsenal.
Renato Sanches - has done really well for Lille. Injury issues still a concern for him, but talent wise I'm convinced he's up for it now. Different style but would improve our midfield nonetheless.
Laimer - similar to Renato - class player, different style to FDJ. Solid and safe in possession, huge engine.
Lovro Majer - Proper midfield maestro. Not a great defender but brilliant on the ball, very creative. As one of two 8's in front of a true #6 he'd be great in the PL for my money.
Would love Laimer but looks to be Bayern bound.
No one in my list is as good as FDJ and most unrealistic but I'll give it a go:
Nunes from Sporting would be my top choice, truly a box to box player that can do just about everything.
Neves though likely overpriced
Soler, but unsure why hasn't ever stepped up to a bigger team
Barella, probably will never leave Italy
Less proven gambles:
Camara from Salzburg, looked a monster in the UCL
Kone, inconsistent and young but had a crazy run of games this year where he looked like one of the best young players in the German league
Thurman from Nice is up and coming but probably not our level yet, has all the physical tools
i think Internet fans are getting pretty good at spotting the good players early!