Stacking reflective materials - UE5.5

Well, no worries.
The problem at the core is the transparency - the engine doesn’t sort them right and offers no way for you to direct the priority (well check on that might be different with newer development).

If you make your materials non-transparent, they will sort like you expect.
The mask/transparency for them will look a little different ofc, but you have to make do with what the engine can do in this case…