Is there an Ubuntu documented build to run on 2018 MacBook Pro?
This is something that must be extrapolated as the 2015 through 2017 MacBook Pro's aren't vastly different than the 2018-2019 MacBook Pros.   The key functions:

* Audio                   → Not Working
* Suspend &amp; Hibernation   → Partially Working
* TouchBar                → Partially Working
* TouchID                 → Not Working
* WiFi                    → Working on 13,2; 13,3; 14,2; 14,3


These will follow with the same statuses as MacBook Pro models 13,2 through 14,3 as noted.

Now, one very safe bet is to go for the main LTS build of Ubuntu as it is exceptionally well documented and has several dedicated support sites as well as this Q&amp;A site.

Now, it's entirely possible that nothing works because of the new T2 chip that encrypts and controls the storage meaning you have to disable all boot security unless Apple signs your OS.  Given that, running Ubuntu on a 2018 and beyond MacBook Pro computer will be limited to virtualization - VirtualBox, Parallels, VMWare, etc. (IMO) this is a better path to pursue.

You can disable external boot and run externally, but the T2 SSD aren’t available for any OS other than Windows or macOS in 2020 due to secure boot and lack of drivers for the T2.