I’m trying to copy a saved csv import configuration from my sandbox to production account, but I keep getting this error while it is ‘calculating dependancies’ --

These generally don't work well in copy to account. Better to just open in one browser and then log in a different one and manually copy

Get these with saved searches too. However, if I download the object via SDF and upload via SDF it works fine? I thought the process would be similar or even the same with copy to account in the back end.

No - it's the same underlying tool, but copy to account is doing the code writing for you - checking dependencies for auto inclusion in the record. When they figure out that piece, it will be amazing. Until then, it's very hit or miss