I will let you know. My ISP modem is in bridge mode, so it only works like a modem. I don't mind to have two times Moderate if we can join eachother and other friends.
If only one PS4 is in use NAT Type is always Open.
Thank Fraser, I did set it up like this. But when I use UPnP instead of Port forwarding I don't need to fill in these ports, right?
Also we're playing 99% of the time Gamebattles, so we don't have the Geo-Filter on anyways.