How about:

• use (English) = a habit / habitude (French) to replace “usage”
• function (English) = purpose / fonction (French) to replace “usage”
• in use (English) = something you utilise / en usage(French)to replace “usage”
• practice = custom = tradition (English) / to replace “usage”

I hope it helps.

This could be a difficult strategy because at the end of the day, the translation is only marginally wrong and it’s easy to find monolingual or bilingual dictionary entries that seem to justify it. Take the first couple of definitions of “usage” on Wiktionary:

1. The manner or the amount of using; use.
2. Habit or accepted practice.

Showing why (1) doesn’t apply to your case seems hard. And if you go to respectable dictionaries like the OED, which does list “practice/tradition” before “the manner of using”, you’ll have to make a subtle argument about why the order shows that your colleagues’ us(ag)e is invalid…

But if you feel you have to go this route, I suggest:

It’s as if you said « pratiques avancées » or « actes d’utilisation avancés ». Close but not right.

The tack I would rather take is simply:

“Usage” sounds odd there in English. In this context, where you mean something like “function” (« fonction »), we just say “use”. For example, “To what use will you put this software?”