The phrase "appear to be posing" is correct and usable in written English.
It can be used when describing someone who seems to be pretending or presenting themselves in a certain way, often for effect or to create a specific impression.
Example: "The actors in the play appear to be posing as characters from a different era, adding depth to their performances."
Alternatives: "seem to be pretending" or "look like they are posing".
All those unidentified musclemen who tested positive, whoever they are, appear to be posing for advertisements in a bodybuilders' magazine, but they're really posing for "hazardous to your health" advertisements.
He does not appear to be posing any threat, nor does he attempt to resist, yet he is hit numerous times by an officer clad in riot gear who appears determined to beat him to the ground.
And the camera's presence in an image can seem part of its strangeness, as with Ms. Fremson's shot of the gentleman photographing a photo-mural by Cindy Sherman that makes Ms. Sherman, costumed as a circus juggler, appear to be posing just for him.
In another image, Oprah Winfrey appears to be posing with two arms by her side, while a third is gripping Witherspoon round the waist.
For us, it would be unthinkable for the state to authorise the killing of another unarmed person, who appears to be posing no immediate threat, without that officer properly being held to account for his or her actions.
His hands often seek a settled position around his face as he talks — balled into fists on which he rests his chin, or spread beneath his jaw, so that he appears to be posing but is really just paying attention.
The growth of logging in the rain forests of central Africa appears to be posing a long-distance threat to one of the world's most important nesting grounds for several species of rare sea turtles — the coast of Gabon.
THE NEWS Logging in the rain forests of central Africa appears to be posing an unexpected threat to one of the world's most important nesting grounds for several rare sea turtle species on the coast of Gabon, scientists have found.
