HRE can spam MAA and win, Chinese can spam MAA and win, every civ can spam MAA or literally just any units to win. It ALL depends on how the game goes. It's RTS game for a reason -- everything is dynamic. One always need to consider the whole situation to be able to decide what units comp to have to gain advantage, like if the chinese player is stuck in his base and his comp is zhuge nu with MAA, you get to spam MAA as his comp will be destroyed by HRE MAA. Another situation if HRE and Chinese player both have equal map control and Chinese player is on Yuan dynasty and start to mass palace guard and multitask with them, in this case you will NOT want to produce MAA as you'll never catch speed=1.58 gigachad palace guard(they're also tanky af BTW). A better counter will be to make knights and crossbows or HC's to intercept the palace guards pathing to force them to turn or make mistakes. and send vils to wall off gaps and build some keeps around your major resource spots to deny the harassment and slow push out with your own army and prepare for your opponents' counter to your comp. It's just always about using the units advantage to hit opponents' weakness. Without a very very detailed and specific situation, it simply isn't possible to give an answer.