I like listening to foreign metal, especially Japanese. I want more music like them but I don't really know how to find it.
I don't think there is another band like Maximum the Hormone, but if you like Japanese metal then you could check out these bands (if you don't know them yet):
Blood Stain Child
Dir en grey
Dude, I love the Japanese metal scene. Unfortunately, not many bands from Japan are like MTH. Girugamesh, Deluhi, and D'espairsRay are probably the closest out there.
there is nothing quite like MTH, but some bands that I get a similar vibe from are as follows, (I also think it's very likely that MTH are influenced by a few of these bands)
System of a down (you already know this one, but I think it's fairly obvious that MTH are big fans of theirs)
Look what I did http://www.youtube.com/watch?v=ygt0RSD6VKw
Protest the Hero http://www.youtube.com/watch?v=vKZ-eKBJ9dw
The Dillinger Escape Plan http://www.youtube.com/watch?v=rogDmn02Xbw
Dir En Grey (this is the only other Japanese band I like, but you already heard this one)
ONE OK ROCK 「Liar」
very good band.
sorry, This band is rock but not metal.