Hi all, just a heads-up about a new kid on the... block 
Tinkercad is diversifying into block-based 3d programming, currently in beta: https://www.tinkercad.com/codeblocks
Many bugs left, and there's a lot of features missing, but it has potential.
Looks like they're using the same blocks library as Scratch 3.0 - maybe Eric has more information?