This is what, the lead designer of the game had to say about crafting our own melee weapons. You can now build and equip your own weapons as per your liking and use them in combat. One of the players went on to ask if there were any dedicated melee weapons and this was his reply.
So, it seems we will start with omniblade and then we can tweak the weapon and build our own from it. We have had weapons builds with Bioware’s previous game Dragon age : Inquisition. However, I reckon the build of the melee weapons in Mass Effect, will be totally a different scenario, coz it’s staged in space and doesn’t involve dragons.
One thing, that shouldn’t happen is, the devs creating a melee-centered character, which might not make sense, coz the opponent might put a hole in your character’s head with their guns while you run at them swinging around your whatever melee weapon.