I am aware of:

BBC Micro:Bit https://microbit.org/

Crumble https://redfernelectronics.co.uk/crumble/

Codebug http://www.codebug.org.uk/

The BBC Micro:bit uses python or MS MakeCode (which is a bit like Scratch). The Crumble uses its own software, which is a bit like Scratch or Blockly. The Codebug uses Blockly.

It's possible to use Blockly with NodeMCU boards (I think, I haven't tried this yet).

This feels like quite a short list. What boards am I missing?