This may be an unpopular post but....
I find it quite shocking that this thread is contemplating all sorts of dietary 'supplements' to help people climb rocks. For sure - take training seriously - but to this level?? I'm presuming none of the posters here are elite rock athletes - so doesnt this all seem a bit overkill?
*shrugs*
On the one hand; different strokes for different folks. You don't have to be a pro with all the insta sponsors to want to maximise your climbing abilities, so if nailing your nutrition is one of the things that will get you there (and it's surely indisputable that it is for most people), then why not?
However, my experience with supplements is that they actually had the extremely negative effect of allowing me to train more than my body, and particularly my fingers, could handle; with the natural result that I picked up multiple finger injuries.
I've had much better, slower but more consistent results by keeping it simple, eating good whole foods, sleeping lots, drinking lots of water and playing the long game, rather than trying to turbo charge my "training performance" with all sorts of powder. Saved lots of money too.
To answer the OP's question; banana and a coffee.