Add non-tracked masks to source effects

I understand why you can’t add masks with tracking to source effects, but why can’t I just add non-trackable masks?

Use case: I have a timeline with clips from 10 different interviews. Every time Subject A’s interview is used, I want to create a vignette using Lumetri with an ellipse mask. The mask never moves or is tracked, because the interview shot is a lock-off.

Currently I need to copy and paste the Lumetri effect to every instance of that clip on the timeline, which is slow and tedious. It also means if I want to tweak the mask or the effect, I need to remove it again and re-copy/paste.

Adding the effect with a static mask as a source effect would solve all of these problems.