Here’s an interesting update - looks like Moxy could start early (supposed to start in 2021 with A220s) with some used E190s from Neeleman’s Brazilian airline called Azul which is phasing in some new Embraer E2s. Here’s the article:

https://theaircurrent.com/airlines/neeleman-plans-jump-on-moxy-with-outgoing-azul-e-jets/