I think the issue is that the strings will only have physics applied after trying to go in game mode aka when simulating a game on UE4/5. So simply click Alt-S on your computers keyboard to test it. If that doesn’t work you can also try the solution I located in this video. UE5 preview 2 Fixing MetaHumans Issues Part 1 - YouTube (Around 7:52)
Oh and I guess you can get it to work in Sequencer, but I really don’t mess with it for the animation stuff I play with out on UE5.
So I’m here due to looking for a solution for this myself, and I found one, although idk if it’s a permanent fix. If you’ve already successfully moved all body parts over from your metahuman into your Character BP, and have used the Set Leader Pose Component node in Construction Script, I deleted the Torso variable that I originally plugged into the Target pin, compiled saved n played and the drawstrings are dangling freely now! I know this is an old post but hey, I ended up here looking for solutions so I figured I’d share what worked for me (at least for now)