Been playing WoW on Linux for 3 years, and a few other times before now as well.
WoW works very well on Linux. You lose raytracing but otherwise everything works. Addons, battle.net, raiding, PvP, you name it.
There is no official client but frankly there might as well be. You won’t be able to tell the difference.
One thing I would strongly recommend you to do is to install Lutris.
You will find it in your package manager most likely, depending on your distribution. There’s various app stores as well like Discover on the KDE desktop, or Pop!_Shop on Pop!_OS, etc.
If all else fails, check your distros from here and put the commands into a terminal, but probably not necessary: https://lutris.net/downloads
Once it’s installed you’ll have the ability to search for games. Search for Battle.Net and you’ll get a wine install with battle.net in it that is compatible with all your Blizzard games (careful with Activision games though. Anticheat issues!) and from here you just install and run the game.
Addons will be located in $HOME/Games/battle.net/drive_c/Program Files (x86)/World of Warcraft/_retail_/Interface/Addons
Where $HOME is probably /home/yourusernamehere.
I might have made a mistake in the above but it should be broadly correct. Shouldn’t be too hard to find.
Lutris also has many, many other installers for various games. It comes with Retroarch so tons of emulation possible, it does battle.net, Steam, GOG, Epic Games, and many more. It’s kindda like a game manager that also happens to have install scripts to make it easy to install non-native games.
And not only does it run, it runs well in DirectX 11 mode especially: (DXVK is for DirectX 11, VKD3D is for DirectX 12)
Have fun!