While I agree that we (fellow Frenchman here) tend to overtranslate, some of our portmanteaus are kind of clever.
My personal favourite is illectronisme, a combination of illettrisme (illiteracy) and électronique (electronic), to refer to people who are not good with computers.
My favourite is autof = selfie. It’s auto-photo, but if you pronounce it, it’s photo said backwards — because you use the hold the camera backwards or use the front-facing camera.
Not only will there be tons of small mistakes with nouns/verbs as you mentioned, but maybe worst, there is often "overtranslation".
Some words are well established as technical jargon in English, and should _not_ be translated.
- "cloud" -> "infonuagique"
- "email" -> "courriel"
- "freeware" -> "gatuiciel"
...