For mostly Structured Text code and Studio 5000 (aka Rockwell) programming, I use the L5X files and remove a lot of stuff that is making diffing and merging annoying and split the big file into one per AOI (aka function) and program.

See https://codeberg.org/aliksimon/l5x-git-tools for the code that I use as a pre-commit hook.

It has several customization options in the hope that it can be useful for others as well.

It makes unnecessary merge conflicts very rare but does not help much with graphical PLC languages.