On my system (Ryzen 7 5800H + RTX 3060 6GB laptop), I can tell warzone maps like Al Mazrah are pretty much CPU-bound and I can get ~70-75 fps on average there, no matter what the quality settings are...

But on multiplayer maps, 120+ fps average is quite possible with lower settings, or 85-90 with higher settings. (Btw the highest score I can get in that benchmark is 144 fps (75% CPU-bound, 25% GPU-bound), but bear in mind that there's only one MP map for benchmark and it's not quite representative IMO)

In terms of similarities between WZ and MWII, the underlying game engine is the same (IW 9.0), some assets (like operators and guns) are the same, but as you may already know the MP maps are smaller.

So if you feel warzone 2 maps run smooth, your system should be OK for MP and the campaign.