As per the game's startup screen, it's indeed by Waixing.
Here's the ROM for Huo Yan Wen Zhang - Sheng Zhan De Xi Pu.
I do have the Fire Emblem III title screen hack variant as well, but it's a bad ROM. I haven't been able to get that work on FCEUX (emulator closes every time I start up the ROM), Nestopia (gives malformed or unsupported mapper error), and NintendulatorNRS. I apologize greatly, but I didn't want to give you a non-working product.
I'll still keep looking for working ROM of the hack variant.