D&D 5E Can you transform a magical weapon when you summon it as a bonded pact weapon?

[Mirtek]

it says you create it,

Actually it does not. It says you it appears when you (re)create your pact weapon, not that you create this magic weapon

 

[Mercule]

I'd say definitely not. When you're dealing with raw energy (before binding), you can shape it as you please. Once you've bound a weapon, it is what it is.

I don't know that I'd consider it overpowered to change it so that the bound weapon stays in the non-dimensional space and you just use it's traits to power your (virtual) pact weapon. Slightly more potent, yes, but not insanely.

 

[steppedonad4]

The last time this thread came up I thought the answer was "No" but checked the PHB to get the language exactly right.

I had searched (web) for an answer but didn't see any threads here on it. This is definitely one that I would appreciate a SA answer on.