Is there a British version of the [Lichtbildausweis](https://shop.digitalcourage.de/lng/en/thema/ak-data-retensio...)? It's a custom 'official' looking ID that is sold by an NGO that promotes privacy among other things.
I've never tried to use a false name, but it probably would be easy for many things (utilities, local government) but difficult for others (bank account).