It's finally here, you can now use Auction House on MC 1.13.2 not entirely sure about 1.13.0/1 but it should still work. Not sure what else to say
Note there are a couple of features that are not fully implemented like the 1.8.X - 1.12.X versions.
On the website, where you view the auction data, there will be no image icons since 1.13 no longer uses IDs and the images are named using ids.
There is not Quadrillion support, so I believe the absolute max on the 1.13 version is around $2 Billion.
Other than those two things, everything SHOULD work properly.
If there is any bugs that you encounter while using the plugin on 1.13.2 please let me know so I can fix it. Also note, it's suggested that you use 1.13.2 since it's the latest version, lower versions may have bugs.