Try adding ?hl=en to the URL. A similar situation happened to my wife after visiting Germany, we had to edit her cookies and clear the "hl" parameter (IIRC) because various random Google sites were entirely in German.
They do, and have since at least the mid 90s. But most users don't know how to set this preference, so Google assumes GeoIP is the One Source Of Truth(TM) for language (apart from hl= and being signed in).
How about suing a new fucking search engine, DDG or Bing?!!! Do this for that, that for that and we'll need a college degree on Google searching. I travel so my searches used to automatically transfer to google.cctld. No thanks!