So I know that melee weapons scale off your stamina, but what about their enchantments?
Can you deal additional spell damage as well as your stamina damage using melee weapons?
I'm not quite sure what you mean, enchantments are from glyphs, and they scale with the relative potency rune you used to create it (reporas for cp160)
Weapon enchantments are fixed values based on the level and quality of the glyph used. I don't think they are even affected by CP and other +damage% passives though I haven't tested it (at least their tooltip value is doesn't change).