Hi @aphanotus,
I am the developer of q2-coordinates and am so glad to hear that you want to use this!
With popular demand it could be... I started that plugin as a sort of side project so ideally it should be user-tested more before we could migrate to the "core release". But if folks find this plugin really useful we could definitely migrate it (even though ultimately we are trying to step back from the idea of a "core distribution" and all plugins will be distributed on the library).
This seems like the bigger issue that should be addressed anyway — I never work with docker so we will need to wait for other QIIME 2 team members to return to the office (there is a QIIME 2 workshop this week, so responses will be delayed). Just in case there is a useful nugget of information you could check out this topic — but that's a 2017.12 container so is probably irrelevant if some new issue is preventing installation. Sorry I can't provide direct support for docker issues!
Do you have any other way to install QIIME 2 natively? That is the only immediate workaround I can think of.
Once you do get this plugin installed and working I would love to hear more from you: feedback on existing actions as well as other methods you would like to see in there. Thanks!