Hysteresis in a MOSFET's I-V
I have been studying/working with MOSFETs for 25 years and I've never heard/read about "hysteresis in a MOSFET's I-V characteristics". So in my opinion: it does not exist.

Maybe it exists on a theoretical level but in practice I have yet to see it before I believe it exists.

The only hysteresis that you would encounter regarding a MOSFET is the hysteresis that you add with the surrounding circuit.

Please link to one or more of the articles where you see this phenomenon mentioned so I can have a look myself.