Lumineon 4 Star Pose: How to Complete Stirring Up Starmie Request Walkthrough
The request is to take a 4-star picture of Lumineon.
Guide
Visit Lental Seafloor (undersea) at research level 3.
Take the alternate route to the underwater ruins & go to the Floor of the Undersea cave.
Scan the area to identify buried Starmie. Throw Fluffruits on Starmie (Visible as a gem buried in the seafloor) to lure Lumineon.
When the Lumineon gets near the hidden Starmie, it will spin around, creating a gust of sand (4-star pose) that will make Starmie pop out. Snap a photo of Lumineon at this moment.
Note: If the Lumineon is a bit too far from the Starmie, you could also throw the fluffruit directly at the Lumineon for it to swim over to Starmie.