The idea is the same as always, just UIs have changed
The process of setting a static IP only changed as far as navigating to the IPv4 settings section.
If you consider the actual port forwarding process as "changed" then it will always be changed because each router will be sightly different. Every tutorial should be filled with "see your router manual for more"
IPv6 is mostly irrelevant to port forwarding because I've never seen/heard of an IPv6 only LAN. I've seen plenty with it sure, but not exclusively IPv6.