Battle for Azeroth allied race access across multiple accounts

I have several game accounts all linked with each other as part of one battle.net account. I'm able to share mounts and heirlooms between these accounts.

I'm trying to figure out how Allied Races work with regards to multiple accounts.

The Battle for Azeroth expansion includes several new races each requiring that the player has achieved exalted reputation with the races and completed a specific achievement for each race. The races are available once you upgrade or pre purchase.

On one of the accounts I have a character that is exalted with one of the Allied races and has completed the achievement, can I upgrade a different account and use the allied races on that account or do I need to upgrade the account that has the character to unlock them?

If I upgrade one of the accounts to Battle for Azeroth, will I be able to use the allied races on that account even though it isn't the one that has the character that qualifies to create allied races.

Solution 1:

Allied races along with mounts (some exceptions are the Gladiator mounts from PvP are not battle.net wide), pets, toys, achievements, etc. are all available on every WoW licence under your Battle.net account.