Who is Padmapani?
Padmapani, as a name for Lokeshvara, is very much a Sanskrit language term coming out of the Sutra and Mahayana traditions of Buddhism. The Tibetan language translation of the name Padmapani is not easily found in the Tibetan literature. The name is also not commonly, if ever, found in Vajrayana Buddhism where the forms of Lokeshvara are understood as meditational deities with clear descriptions and meanings taught in the various Tantra texts. The most common Sanskrit names for the deity in Vajrayana Buddhism are Lokeshvara, Avalokita, Avalokiteshvara, Lokanata and Mahakarunika. After that there are scores of names for specific forms of Lokeshvara - peaceful, wrathful and in-between.
It is interesting to note that in the study of Art History the term Padmapani is almost exclusively used with reference to sculpture and not painting.
The general description of Padmapani is of a peaceful male deity, seated or standing, wearing a crown, jewels and heavenly garments, holding a flower, or stem of a flower in the left hand that blossoms at the level of the shoulder. This type of appearance can also be called bodhisattva appearance. Peaceful deity appearance and bodhisattva appearance are the same. Any figure that fits this description could also be called a 'lotus holder' without drawing a connection to Lokeshvara.
A specific description of Lokeshvara Padmapani and a positive identification requires in addition to the characteristics above, Amitabha Buddha on the crown of the head, and a krishnasara deer skin over the left shoulder.