would it be possible to publish an extension for Scratch 3.0 that commands the Makeblock robots from the Web Platform?
The idea is still to use MBlock5 for offline work but also be able to program and share on Scratch with an official Makeblock extension.
Scratch is great to start with and then the next step is just an extension to go on with the physical world
IMHO it will also have a nice marketing effect for Makeblock as there are many Scratchers knowing only Lego.
Current Scratch 3.0 planned extensions are Micro:bit, Lego WeDo 2.0, Lego Mindstorms EV3, Lego Boost. Check icon on https://preview.scratch.mit.edu.