The Alwars (also spelled Azhwars) are a group of 12 ancient Vaishnava saints who lived in Tamil Nadu and are famous for their poetry in praise of Vishnu. The collection of their 4000 poems, known as the Naalayira Divya Prabhandam, is considered by many to be the "Dravida Veda", or South Indian Veda. The Alwars are crucially important figures in the history of Vaishnavism; it is the principles and beliefs embodied in the Alwars' poems that ultimately gave rise to the Sri Vaishnava sect (of which I'm a member).
In any case, one of the Alwars was a Chera king called Kulashekhara Alwar, who was an incarnation of Vishnu's Kaustubha gem. He is most famous for his Perumal Tirumoli, the collection of his Tamil poetry in praise of Vishnu, which is included in the Naalayira Divya Prabandham. (I discuss one poem in the Perumal Tirumoli here.) But I just found out that in addition to his Tamil poems, he also composed a Sanskrit poem, known as the Mukunda Mala Stotram, i.e. a poem meant as a garland for Krishna. You can read it here; it's quite beautiful.
So my question is, was Kulasekhara Alwar the only Alwar who praised Vishnu in Sanskrit, or are there Sanskrit poems composed by other Alwars as well? One of the Alwars, Periyalwar (whose work I discuss here), was the chief priest of the Srivilliputtur Temple, so he would have been quite educated. So did he or any of the other Alwars manage to write in Sanskrit, or were their poems limited to Tamil?