Can you rename config files for mods?

I want to add EpicFightMod and the Epic knights mod but the best way I've found to add compatabilty is to rename the Epic Knight mod's config file to the EpicFight's config file. Can I rename names of config files? I can't seem to find a(n obvious) button to rename any file at all. How do I rename things, or is it simply not possible at all?

so to get the config, do I get it from my .minecraft? I don't see a download button so I assume that I gotta get the file from my own computer

turns out that config file doesn't generate on 1.12.2. Thanks for the help anyways, now I know what to do in the future