If everything in the initial code is 300% covered with excellently documented tests that should be minimally changed during transition (if transition don’t reveal any corner case tests were missing, maybe the transition is not such a bright move after all), that seems a possible thing to consider.

Otherwise it really sounds like a recipe for unnecessary huge risk with dubious expected positive outcome.

Not saying don’t have fun, but on the other side maybe not with the core product of you cash cow already?