That would be my problem right? In my understanding, if I get some remote device to dial into my home network through a PiVPN running in my home network, i believe the remote devices can access and ping home devices, but no home device other than the PiVPN can ping them back? Right?

Sorry, but I’m a bit lost with these specifics. I currently have a reverse proxy (nginx) publishing some of my apps running locally on my home server. Where should I put the reverse proxy? On the remote unreachable server, or? And how would the tunnel go?

Oh wow, I’ll have to try this! Can then the virtual IPs be pinged in Wireguard VPNs? (I mean, PiVPN is simplifying Wireguard anyway).