15 weapon question

Before I npc. Is there a way to trade a 15 weapon I won't ever use for one I will? Like a wired lance for a Millioraj Dusk.

only certain series of weapons can be changed to another type like Trailblazer and Atlas EX, those who can be changed are done by Zig if is not one of those series then no it can't be changed to others and the only solution will be to sell it, dismantle it or use as fodder for affix or exp

Only certain weapons can be exchanged via Zieg's "Weapon Category Change" menu option such as Atlas, Atlas EX, Lightstream/Trailblazer, and Liberate/Rivalrate so far.

The rest are either weapons you will want to hold onto for their power (like the Millionaire weapons for basic gearing at the minimum) or are already end-game viable weapons (such as Serpen Plenzer/Serpent Prenzer for the Jet Boots). The rest are things you would dismantle for the Platinum/Diamond resources needed to craft the new Episode 6 end-game weapons.

sigh It was a faint hope but I'd rather ask something I am almost sure of rather than think I know for sure, doing something unreversable, then finding out some out of the way npc I missed could do it.

Not gonna go through that a third time.