tayyare is right, it shouldn't hurt to give it a try. Even original, period-correct "MS Mouse" mice shipped with serial-ps/2 adapters.
At least the models from the 90s onwards, if I rememeber correctly. My dad had such a mouse in '95 or so.
Edit: Andy1979 is also right. Some more recent models don't work with these adapters anymore.
That's because the simple adapters are just doing mechnanical conversion. The protocols (ps/2,USB,serial) are
processed by the mouse itself. Except for modern mice adapters, which do contain a tiny ps/2-USB converter chip.
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