i explored that at some point in the past and it was basically getting the bundle js filed from unity webgl exports and feeding them through some tools like ILtoCPPdumper but the technology changes so fast and you get heuristic results that are hard to translate into proper edits/aobs.  There is no proper wasm tooling (that i know of )yet either to tackle the actual in browser stuff so it is a tiring process of trial and error and code structure goes out of whack with flat memory layout ie no property access / methods signature not being easy to infer
Really made me appreciate the work the guys before me did to pave the way for flash. If you achieve something share it back