If we keep playing in a 4-2-3-1 formation next season, we surely can't rely on Adli and Diaz. I like Adli from what I've seen. He's a talented player, but we can't rely on him on CL-level and in high profile Serie A matches. Diaz isn't good enough right now and will probably never be good enough.
I don't think it's too far fetched that we might see a slight change in formation next season. Probably a 4-3-3 with more dynamic midfielders.
While I
worry that Adli will need time, perhaps a Tonali-like gap year, I don't think it's impossible he hits the ground running. If we've won (and dominated) big Serie A matches with Brahim and Krunic, I don't think Adli will be a problem. In the CL? While the boys froze (initially) at Liverpool, against Atletico, they came out roaring. Each game in our group was a quarter-final level, and I think they did well for their first year.
Plus, Renato, if he does come, will add a huge dimension and flexibility to our game. I think we have shown 433 looks already, while I might not rate Brahim I am much more bullish on Adli. I think he's going to surprise people.
Even if we had just Adli there, with Brahim and Krunic to back him up, not even counting Renato, having an actual RW would fundamentally change the way teams play against us and the space would open up for us. RW has to be priority number 1, without question.