As you may have noticed, recently during the World of Warships common test, mods has stopped working. It is because the developers decided to disable them, or rather disconnected the res_mods folder. It was done most likely that people would not distract developers when they had errors or bugs in the game due to mods. During the common test, the task is to find the bugs of the game itself.
But we usually go into the common test in order to just play a new version and test the ships. For this mods are quite necessary. Fortunately, it’s very easy to return the mods work, as I said above, the folder in which the mods is usually put is simply disconnected there.
To include the folder res_mods, you need to go to the folder with the game, find there the file paths.xml and edit it. You can open any editor and add a line res_mods / 0.8.1 after the profile line.
It should be like this

res_mods/0.8.1
res_packages
res
res_dlc

Perhaps it seems complicated to you, then just download the finished file and copy it into the game folder with the replacement.