So I just figured out how to successfully install Windows ME on QEMU despite being seemingly impossible: I installed it as an upgrade from 98SE (may not be necessary), then booted up to safe mode (which told me that it was a drivers issue), removed vmcpd.vxd from HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\VMM32Files (rip floating point exceptions) and changed the file extension for drvwq117.vxd and drvwppqt.vxd (rip tape drive support). It Just Works™️
The tape drivers are found at C:\WINDOWS\SYSTEM\IOSUBSYS. Apparently you can restore vmcpd.vxd after install and the system will do just fine (not the tape drivers tho). And according to https://jeffpar.github.io/kbarchive/kb/136/Q136255/ it may be possible to patch the vmcpd thingie without even manually editing the registry, just going to the device manager.
Tooted this so I can help others who are interested. I'll now return to my usual hiatus
The social network of the future: No ads, no corporate surveillance, ethical design, and decentralization! Own your data with Mastodon!