I don't think Cunha replaces long shooting of Schär. Schär gets into those positions because he is a centreback.
I see no point getting Cunha, only if he could be moulded in to some sort of right winger/no 8/striker -hybrid which would allow him to cover few positions.
With Cherki I see the technical ability and 1v1 skill, but I doubt he has the workrate or physicality for Howe's team.