Hey i discovered something thanks to reddit, you can change the controls from Ultraumbral to normal buttons, you need to do this
"Head to the Gamefreak office in Hea Hea city and talk to the Aether Paradise Scientist.", then change it, finally starts the shiny hunting
"Head to the Gamefreak office in Hea Hea city and talk to the Aether Paradise Scientist.", then change it, finally starts the shiny hunting