Was thinking fairly straightforward temporary weapon enchantments. Something you would need a tier three alter and archpriest to create, would not consume the alter or priest. Maybe put the weapon in and offer zeal and other materials to bless the weapon.
Mitra: blessing of holy fire- lights blade aflame and gives each hit a short damage over time burn, also functions as torch
Set: snakebite invocation- blade is obscured in poisonous aura and causes noxious gas buff on hit, hurts wielder if no sandstorm mask is equipped.
Yimir: blessing of frost- icy black aura around blade, each hit drains some of opponents stamina also grants resistance to heat.
Yog: corrupted blade- blade pulsing with corruption, each hit stacks a small amount of corruption on opponent, you very slowly gain corruption over time while using.
Derketo: goddess kissed blade- weapon wreathed in blue light, adds a small amount of lifesteal scaled with damage done
Jehbal Sag- blessing of the beast- weapon has yellow glowing clawmarks on it, each hit landed without taking damage increases your damage done up to a cap
This would go alongside the crazy new arrows really well, and add an extra layer to worshiping the gods and melee combat.