You are in a very niche area, fudging to make things work well will not be easy or cheap, maybe reappraise the whole thing.
You think? Could I not just get 7800 levers? Or would that not work with the derailleurs?
Yes a 10 speed set up will work with a 9 speed derailleur but will not be optimal.
@andrecustodio56 started
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You are in a very niche area, fudging to make things work well will not be easy or cheap, maybe reappraise the whole thing.