Client: WoW Classic Era (SoD)
Steps to repro: check both factions’ PvP gear vendors. I did just verify this information by checking these vendors on the live servers.
Alliance PvP healing boots (Sergeant Major’s Satin Boots) are incorrectly statted. They give +13 Int (no Stam), while the Horde version gives +12 Int & +13 Stam. Compare further to the damage versions of the cloth boots, which both give +12 Int & +13 Stam. Finally, all other PvP gear that I checked seems to be identically statted between factions. Therefore, the statting on the Alliance healing boots seems clearly to be a mistake.