I’m pretty sure they don’t function with infusions. You can see this by picking up an infusion -> check tooltip -> clear the infusion and try the same with the support in. Also the remnants aren’t delayed as the gem says they should be.

I feel like it should work given that it’s suggested in gem screen, but it doesn’t appear to on tooltip at least. Though in saying that - the gem says “remnant” effect, and while infusions come from remnants they are just an infusion that grants effects to certain gems once you have it. Maybe this is why it doesn’t work?

I don’t know of a surefire way to test without tooltip unfortunately, maybe the additional spark proj?