No, this isn’t possible, that’s not how mo or po files work.
A po file declares which locale it is for, and gets compiled into an mo file. You can’t store more than 1 locale in the same file. Each file represents a single locale.
Keep in mind that these files aren’t a WordPress thing. They’re a gettext thing, and are used in lots of different applications, including other CMS’s and even programs that have nothing to do with websites and servers.
So there is no WordPress based solution to your problem. Your search should continue elsewhere, specifically in the area of tooling