https://wccftech.com/wow-dx12-battle-for-azeroth/

WoW DX12 support appears to have finally been added to the game through Battle for Azeroth pre-patch 8.0.

Although support for the DX12 API wasn’t mentioned in the release notes for yesterday’s pre-patch, eagle-eyed Reddit user ‘jaykresge’ spotted support for the API in the game’s advanced graphical options. In previous versions, players were able to select between the DirectX9 and DirectX11 Graphics API, but Blizzard has now removed the DX 9 API option, and has added a DX12 option. Back in January of this year we already reported that the Battle for Azeroth Alpha possibly revealed the addition of DX12 support.