I also have this exact same issue that's been bugging me since the launch and is why I play bf6 a lot less than other games. I have an RTX3000 mobile graphics and 16 core (e2286m/i9 9980hk) intel processor. All drivers, bios and settings are up to date and overlays like Nvidia's are closed. On the first launch the EA anticheat runs, I open bf6 and get choppy FPS around 30-55fps. If I attempt to play a game it's a stuttery laggy mess I have to reach the start screen, close and relaunch bf6 to get a stable locked 60-65 or as high as 80fps every single time. I've tried the the fix someone mentioned about adding a few lines to a text file to get 16 threads 8 cores to be recognised reliably because previously bf6 was picking up something random like 12 cores, this has helped FPS stability but does not fix the double launch issue. Bf2042 did not have this issue so this is definitely a software glitch for sure.
