thanks, at least for the first point, those “Fritz Box” Routers are somewhat usual in german, I got my own to have more control over my network…and it does indeed support NAT loopback, I think that is what I had to configure in my previous IPv4 Setup for everything to work. For the rest…I will have to do some research. Although, my IPv6 address starts with 2a02 and is indeed reacheable from the outside, so apparently that is a thing
What I really wonder now…do I really need to actually rent a VPS or is there somewhere in the internet someone who overs IPv4 to IPv6 forwarding as a service. I looked at the Oracle ARM VPS but this seems to be a bit convoluted…and its Oracle Oo