Long since in development, Faerun Total War is finally going to make a first release. A mod for M2TW Kingdoms, set in the world of Forgotten Realms, in the vast continent of Faerun. While our campaign is being reworked, the first release is focusing on custom battles.
Edit: The roster of the Thayan Nation was developed and made between late March 2017 (after the Kingdom of Aglarond had been finished) and early October 2017 (when development of the Empire of Calimshan began).
Both the Thayan Nation/Thay and the Elves of Cormanthyr have gotten these new Centaur Archers as a unique new monster cavalry unit in the mod. The model was created by Assurbanippal, I coded it into the mod in February this year.
They will probably be mercenaries in the campaign.