NOTE: I know this is a weird question and sort of difficult to describe, so hopefully I've done it successfully below. If anything I wrote didn't make sense, please ask and I'll try to clarify the best I can.

I was just wondering if you meet someone from a foreign military where their rank is entirely different or pronounced differently, do you say their language-appropriate rank or translate it into your language?

Here's an example: In the US, all of the lieutenant ranks are pronounced "loo-tenant," but in the UK*, those ranks are pronounced "left-tenant."

So if someone's who's active US military meets someone else who's active UK military, would the former call the latter "left-tenant" or would they go with "loo-tenant" (and vice-versa)?

Additionally, if someone who's active US military meets someone who's active German military (at the rank of oberst), would the former say "oberst" or translate the rank into the English equivalent, which is colonel?

\ I know other Commonwealth nations, such as Canada, Australia, or New Zealand, pronounce lieutenant as "left-tenant" or are at least supposed to do so. In Canada, it's officially "left-tenant," but most Canadians I've met say "loo-tenant," probably due to the influence of American media.*