(There's no video for Polonizator Mac OS 9 (3.5.1) yet. Please contribute to MR and add a video now!)
Polinizator translates all the menu items, system windows and general Mac OS 9.1.x or 9.2.x interface text to Polish and also installs the Central European fonts.
(6.33 MiB / 6.64 MB)
Polonizator Mac OS 9 v3.5.1 / compressed w/ Stuffit
Mac OS 9.1 - Mac OS 9.2.2
Emulating this? It could probably run under: QEMU