I have just purchased a Tab S7+ with the book cover keyboard here in Spain so the keyboard obviously has the spanish keyboard layout. In order to type symbols like € and ? you need to use the AltGR key on the right hand side at the bottom but for some reason this does not work in Google Docs when using the Samsung Keyboard. If I use Swiftkey for the physical keyboard however, it works as expected. Although I'm happy to use Swiftkey to get around this problem, I can only use Swiftkey in tablet mode, as in Dex I can only use the Samsung Keyboard app which means I can't type properly in Google Docs, which is one of the main reasons I bought this tablet.
The strange thing is that the Alt GR key works in all other apps, including the other G-suite apps like Google Slides and Gmail, just not Google Docs. So, I'm not sure whether this is a Samsung issue or a Google issue but I'm hoping someone can help. I should add that I have tried changing all the region settings and keyboard layouts and a factory reset and the problem remains.