How to make a weapon change textures or model when I equip it

[SherifOly]

I mean like if I don't equip the weapon it stays with one mesh or texture and after I equip it it uses other texture or mesh

[IsharaMeradin]

You'd need to have a script that calls some SKSE added functions which can change the mesh and / or texture set assigned to the weapon base record.  However, if it is not a custom item, the change will affect all instances of the weapon.  For a working example of such code see The Huntsman and its unofficial patch for LE.

FYI - I do not recall the exact functions.  However, I know that they exist as I did the aforementioned patch.