It actually doesn't.It does.
Media Molecule's Dreams PS4 Will Be Keyboard CompatibleWhile Dreams will allow you to use a keyboard with the PlayStation 4, it will not offer mouse support. ... The keyboard and mouse discussion was immediately followed by a question about a possible PC port. But Evans noted the PlayStation 4 exclusive will remain just that and said, “No. [Dreams is not coming to PC] Honest!”2018/10/0
KB just for typing stuff I guess. MM said the entire campaign was made with the DS4 and/or moves. No special software or other tool not available to users right now.