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.
