PC keyboard bug (or feature?)

On a PC keyboard pressing simultaneously E+R changes the weapon set, as if I had pressed X. E+R=X. E and R are typically used for abilities, so I often accidentally change the weapon sent when I don’t mean to. To me this is a bug.

you sure it is a bug?

Weapon sets switch depending on the skills used, check the skills you use on E and R in the advanced info section and check for the skill options which weapon sets they use.

Activate the checkbox on both weapon sets to use the skill independent of weapon sets and no switching should happen.