That is just the nature of new in development emulators, it's very very far from perfect, a lot of games simply do not run at all well. The compatibility guide saying it is "playable" means nothing, 1 frame per second is "technically" playable, but of course you wouldnt play it at that speed.
Also 8GB of ram could also be limiting you, i have seen Zelda breath of the wild using 13GB by itself.