Bonus! ;)

Profiles are just Voronoi by Max Smirnov
Function Boolean Isect + native Hidden function "ExplodeMove"
(so just Press Tab then write ExplodeMove or make a ShortCut with the same name)

Of course if you want an "Inset" structure just make that!


The explode move gives a funny result but you must make another little trick for use this structure above!



The little trick... (of course the Cube B is closed! )
Take any volume smaller than A
Maybe there is another tip but this one works fine!