ChunkDeletion

Step in a chunk and it will slowly delete.
Bedrock, nether portals, end portals, end frames, end gateways and obsidian blocks below 30 are left untouched (just the obsidian has this extra rule).
The time it takes for a chunk to delete should be around 160 seconds. (In my demo the time was shortened to 80s)
You need to be op to run the command /chunkdeletion.

Plugin video DEMO:

This plugin was inspired by this youtube video:

YT Video

As always, if this plugin doesn't work on your server you might want to check your Java SE version. I'm using the latest version 13 and I pretty sure plugins compiled on Java 13 don't work well with older versions of Java.
I suggest you stop using Java 1.8 or earlier and switch to 11 (LTS) or 13.