Is there a comparison of EOS vs the Ardor blockchain platform? Ardor has the following interesting features: message sending, assets, data storage, and child chain system.

What equivalent does EOS has as compared to those? In particular, Ardor has the child chain system where tokens holders can use the Ardor network without hold any of the parent coins. Ethereum has something similar in the works called Plasma. What is EOS's version of this?