I bind Journey Map full screen map to Mine Menu, and it doesn't open. Really need it for Vivecraft since my buttons are limited.

Thanks for the report!
Making stuff like this would require a major rewrite of the mod, which I simply do not have time to do.

I made a workaround:
https://github.com/ItsDeltin/keysim/tree/master
Set the Mine Menu option to do a command like "/keysim gui.xaero_open_map" which will open the Xaero fullscreen map. It seems to work with everything.