Can 2 end devices be connected to different coordinators?

A quickie: I have an amazon echo and home assistant with Z2M integration.
I want to know whether an end device can be connected with both coordinators (Echo & Ha)

if not, then what happens to the built in zigbee coordinator of the Echo? (will it be repeater, or try to form its own connections to the zigbee devices…)

Whats the best way to go about doing this. Essentially I want to have some devices connected to mqtt to appear on Alexa.