The Crimson Binome
Hero
Actually, 5E does include magic weapons that lack a bonus to hit and damage. I think it's the Flametongue which does extra dice of damage, but which lacks any bonus to hit. It would qualify as a +0 magical weapon.I would bet that most DMs would say "no", because based on an interpretation of implied intent that "magical weapons" are things that have a +1 or better bonus to hit. Now, I personally think that a +0 magical weapon is perfectly logical thing to exist, even more so with 5e flat math. D&D has not yet gone that way.
At least, if I'm remembering that correctly. I don't have my books at hand.