> That said, is there an easy way to run software in "big endian" mode on any modern computer?

QEMU userspace emulation is usually the easiest for most "normal" programs IMO. Once you set it up you just run the other architecture binaries like normal binaries on your test system (with no need to emulate a full system). Very much the same concept as Prism/Rosetta on Windows/macOS for running x86 apps on ARM systems except it can be any target QEMU supports.