Posing in English is pos or pose?

The correct word for this situation is "pose".

"Pose" is a verb meaning "to pose" or "to pose." For example, when a model poses for a photo shoot, the photographer will say, "Pose for the camera." In addition, "pose" can also be used as a noun to indicate that someone is posing in a specific pose. Posture or shape.

And "poss" is not a standard English word. In some cases, people may mistakenly shorten "pose" to "poss," but this usage is not common and is not considered a correct English expression.