Strictly RAW, is punching someone with a crossbow a melee attack with a ranged weapon? [duplicate]

I’m exploring ways to combine the Crusher feat with a melee rogue-paladin, and have come into a conundrum- without using my busy bonus action to two-weapon-fight with a club, is there a way to get bludgeoning damage with a melee rogue?

This is my best attempt- using Tavern Brawler to punch people with a crossbow as the strangest of Improvised Weapons. As this is just a rules exploration unlikely to see the light of day, RAI isn’t very relevant here.

RAW, will punching someone with a crossbow allow it to be a melee weapon attack with a ranged weapon, letting me use sneak attack and smite?

Edit for clarity: Unlike questions regarding thrown improvised weapons which outside of being improvised weapons notably lack the finesse or ranged properties, crossbows clearly have the ranged property. This question isn’t about if improvised weapons give it a new property, but rather if they retain them.