this mod includes every single stage bgm (as of now) from tekken 8.

How To Install

• download and extract the tekken 7 jukebox tool into a folder
• in that folder, create a new folder called "BGM"
• then extract the folder inside the "Tekken8StageBGMPack.zip" file into the BGM folder
• from there, use the jukebox tool

Secluded Training Ground BGM :

https://tekkenmods.com/mod/3125/tekken-8-secluded-training-ground-bgm-reina-s-theme

yes, this mod does include the secluded training ground bgm