I went through spinning up a new vm running Ubuntu 19.10 the other day and so far I've only run into the following problem:
At least using Workstation 15.5, it doesn't like Workstation's "Easy Install" functionality. When setting it up make sure to chose the option to "I will install the operating system later," as noted in this answer I dug up.
Other than that I haven't really encountered anything out of the ordinary (yet). I'm not sure what your use case is, however I've been using mine in an application development capacity for compiling code that's designed to run on debian-based distributions. So far things have been peachy with running everything from the JetBrains Toolbox (as well as the traditional terminal commands for just using a text editor/GCC) but YMMV, as the saying goes.
I hope that helps at least a little bit though!
I was curious, and installed Kubuntu 19.10 desktop standard load on Workstation 12 Pro 12.5.7 -- and with caution to the wind I did the express install, 2 cores, and 1 GB RAM.
It had trouble rebooting after install, and would not boot up, so I poked around and booted into firmware. There I noted the that large disk access mode was set to DOS rather than other. Toggling that let me boot normally, and while I haven't examined too closely, things seem to work.
Hope this helps