Is there anything in canon other than the 4th Trek movie that refers to T'Plana-Hoth the matron of Vulcan philosophy that tells us who this was. I believe I read that the Vulcan ship in First Contact was named that.
T'Plana-Hath has been used as the name of two ships in canon: the Vulcan ship in First Contact and a starship in Discovery. Other than that, she's only referenced by her quote in Star Trek IV. In RPG material, she was touted as Surak's teacher, and therefore a precursor to his philosophy.