Problem is, when I go to launch fallout3.exe on the host computer (i5 5570, 4GB RAM, onboard graphics), the launcher comes up and wants me to install the game. Then, when I quit, just move the saves back and overwrite them, and leave as little trace of Fallout 3 on the host computer as possible (I figure CCleaner will take care of this). So while GOG Galaxy may have cloud saves (I mean, I know it does), what I want is to be able to plug my portable SSD into a computer's USB 3 port, open the GOG Games/Fallout 3 directory I've copied the installation folder to, launch the launcher, quit the launcher, dump my save games in the folder it just made (I've copied them to the SSD as well), relaunch the game, and pick up where I left off.

It's kind of like a big flash drive that is faster than any hard drive. While that may or may not be true, what I actually have is a portable SSD. But then I got to thinking, Fallout 3 was made for 2008 computers, it should be able to run off a USB 3.x flash drive. So, the main reason I bought Fallout 3 on GOG was because I didn't want to install Steam on my laptop, which can play Fallout 3 (and Skyrim, but not Fallout 4 or Skyrim SE).

Fallout 3 google drive