Stupid question but can you use a 24 hole hub with a 20 spoke wheel?
You could. It would likely be 12 spokes on the drive side and 8 on the non driveside. People ahve done stuff like this but its not going to give as strong and durable a wheel as a normal 20 spoke or 24 spoke.
Styrrell
Hub shell can be swapped out to change the hole count by someone who knows what they’re doing. I had Wheelbuilder take my 32 hole and switch the shell to a 20 or 24 (I can’t remember). Wasn’t cheap but I like it.