- create a new wolrd and load into it with the items you want to get ride of.
- drop everything (the item you want to delete) on the ground
- return to the menu an ddelete that new world you just created.

That's also the best to go farming for any loot.

Disconnect in your base and create a new world. Load into the new world and farm there. Once done, return to your "home" world and delete the newly created one.
Since you'll spawn next to your bed, you can do that while being over-occumbered too....
This also prevent your save file cluttering because of things you leave on the ground....