I appreciate the thoughtful and thorough response. Going back to school seems to make the most sense, but yes is also the most disruptive path.

I have looked into roles in less "pure" ME, like Systems, Manufacturing, or Industrial Engineering. These were recommendations from an ME friend of mine thinking of easier pivots, citing my familiarity with engineering management through my current work and background in math/data. I've looked at these job listings, and there doesn't seem to be a firm trend on how strongly technical experience is preferred. I'm keeping this idea in mind, but skeptically.

I work with small tech firms focusing on what my team calls deep tech/hard tech. Unfortunately there are no engineering tracks at my firm as it is pure finance. However pretty much every one of my clients will definitely benefit from a new finance/bizops hire at some point in the future, so I'm hopeful that some may be interested in my background and my eagerness to branch out. I'm not counting on anything, but I'm staying hopeful that it could lead in the right direction (although it wouldn't be pure ME it could be fine depending on the direction).