Hey there 
Update from the Marketplace Team:
Unfortunately the plugin is labelled as “Early Access” and as such the submission process can’t even start. I totally understand the policy and therefore I’ll release EA-MCE on Itch.Io, update it with the help of anyone involved in the EA and I’ll submit it again on the Marketplace.
I’ll keep you posted about the Itch.Io release which shall happen soon!
In the meantime, gl hf in your projects everyone