Merge two presets

(There are multiple threads on merging presets, but they are old and/or doesn't work)

I have two presets: the Default, and one called Duplicate.
I want to delete "Duplicate", but first move everything in it to "Default".
There is a "move trigger to preset" menu option, but that means I have to manually go through every app and every aspect (mouse,keyb,named..) and then move every single thing over to Default, which will take too much time.

I exported both presets and look at the JSON, seeing that it should be easy enough to just merge these two to a single "preset", wipe BTT, then re-import.

My question is what is the reccommended way to merge two presets.
I guess, a feature request would be to select two presets, right click and select "merge":


My beloved iMac Pro just died. Black. Dead.
I got a loaner Mac at the service centre.
A rose pink Macbook Air.
With a lawnmower engine CPU and RAM equivalent to my retarded aunts.
Trying to beeteetee everything back to something I can actually code on.