Crediting MH J to AA earns 125%, but with Plat/EXP status you get a 100% bonus. So AA FFP is still the better choice.
Out of which 100% is EQM, whereas MH EQM is 150%. It boils down to if you want to attain status or redeemable miles.
Another thing to note is you'll pretty much only get miles from AA from flights whereas an Asean card will get miles from local hotels etc.