There's no simple way of doing it, short of having two separate EQ2 installations (with each of you using one). You might be able to make a batch file to change them and set it up to run on login (then have two batch files -- one for when each of you logs in individually), if you have separate users on your computer. If you share a user, you could just make separate shortcuts ("His EQ2" vs "Her EQ2") that use batch files to change things and then launch the patcher.
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