The Swap-O-Matic is a diamond hoe that when you hit a block with it the hit block will be swapped with whatever block you have in your offhand. The block you hit will be put in your inventory, or dropped on the ground if your inventory is full. 

My main intention is for this to be paired up with the Build-O-Matic. Say a player makes a huge wall of a single block type with the Build-O-Matic but it looks boring to them, then they can use the Swap-O-Matic to texture it up with other blocks super fast and easy. It can be used in various other building situations too, and I think it's a cool and useful idea for another building-themed wilder item. 

That sounds amazing for texturing. Or changin blocks without breaking redstone. Or letting water fall if you aren't quick enough, which breaks redstone. I like it! :D

Would it auto texture the whole wall or would it just change the single block so you have to manually texture the whole wall? I think an auto texturing tool would be cool for people like me who are pretty bad at texturing

Wonder, my idea was that it would only replace the block you click. Auto texturing would be cool, but perhaps only if it had certain settings, like a no auto texturing mode, to low, medium, and high.

This idea has a lot of engagement and it's clear the community wants this. The plan currently is to assess the difficulty of this item's implementation and, if it's reasonable, to recommend it! I'll let you know if I hear more =D