Magic Lantern Body Technique (Earth-2356)

The Akatsuki members sat down and send out "thought waves", converted into the Force. These thought waves were then picked up by Pain, acting as a kind of control tower. This technique amplified the thought waves and broadcasts them to a specific location through illusionary bodies. The illusionary bodies differ from being mere holograms. While Pain is relaying the members' thoughts, they can have conversation and use varying techniques.

These virtual images looked like the member they represented, the only difference being that they are standing up with their hands in a seal. The images were also transparent, except for the eyes. The images refracted an array of spectral colors, much like a rainbow. Their bodies distorted and flickered, as if receiving electronic interference, and the members' voices are altered the same way.

Source

 * https://naruto.fandom.com/wiki/Magic_Lantern_Body_Technique.