Haha got to appreciate the marketing spiel.

Did spot a great looking free open source tool in Libretranslate which looks promising & cheap to host. I'll keep a lookout if I find anything else that can be hosted.

There actually seem to be no shortage of expensive translation APIs, including Weglot, Transifex, Translite, Dilingual, Smartcat and Crowdin. I wonder if they're all using the same tech under the hood. Crowdin seem to not charge for open-source requests although would be an extra online dependency.