We had PC emulators on the 68000 based Atari ST in the 80s. No extra hardware needed, but very slow! And I'm sure that emulators was a thing from the very first computers.
There were pc addon boards for this reason for both Amiga and Atari but they were expensive as they were basically a whole pc on a board.
In addition to being a PC board, it also doubled as a memory expansion and RTC when you were using the host Amiga system.
http://bitsavers.trailing-edge.com/pdf/dec/catalog/Digital_U...
But hey, MS-DOS 6.2 and Windows 3.1 would have at least both fit comfortably on a single TK50 cartridge or 9-track open-reel tape, so at least you weren't stuck in front of the console swapping floppies waiting for the products to install.