If Nico Williams comes I don't think anyone will be marginalized between Raphinha and Olmo because these three players will really help the team with the rotation that can be done by Hansi Flick and these three players can play in different positions, Olmo in the middle, Nico Williams on the wing and Rapihna can play a little up front so there is also a possibility that the three can play together.
It is likely that Olmo will be their cover. Yamal's individual skills with Nico Williams are good and the two already know each other's way of playing so when to run to open up space and how easy passes they reach are already able to read which will make it easier. That's the advantage they showed while strengthening the Spanish national team so it is appropriate for Barcelona to dare to make an offer as said by someone above.
If the three can be played together, then Lewandowski's position as a target man will change and indirectly Lewandowski's position will be threatened because there will be a change in formation. 4-3-3 will probably be the formation next season because currently 4-2-3-1 is still Flick's mainstay formation.