I offer my apologies in advance. This is a somewhat weird question to ask here since it's probably somewhat outside this community's wheelhouse, but I inferred from someone else's wisdom that this may be the best place to ask it. That said...
Assuming you're inside an external app with a path to the WoW installation, what means are there (if any) to get the interface version that WoW install is expecting for valid add-ons?
Sometimes, you can just get the file version info for the WoW executable and format it like this:
For example, that works with the Classic Beta because its current file version is 126.96.36.199406 and its current interface version is 11302. However, it does NOT work with Retail because its current file version is 188.8.131.52981 and its current interface version (I believe) is 80100.