Great that your using Vbox
🙂 Not sure if Qemu does Win95/98.
Win95/98 is actually a shell on DOS, so if you can boot DOS, you can boot them. In the cobwebs of my mind, I can't remember exact details but did do this for many years, using loadlin (a DOS boot loader for Linux).
In my earliest days I even retained a DOS partition (for firmware updates) on commercial UNIX systems. Not the greatest of ideas in retrospect but can be done.
😉
Note that many ethernet adapters will respond using very basic drivers, not necessarily the exact one for the card. Brain's a bit fried at the mo' but E1000 rings a bell. Could do some research/trawl my memory, if needs be.
The command 'nice' will limit the processor cycles used, so theoretically it could be used to initiate Vbox/Qemu to restrict speed. I haven't investigated this however.
Might provide you with a search parameter. :-)

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