In Lincoln's fantasy about being at the grown up table, Luna, like everyone, dresses in fancy attire. Her outfit consisted of a sleeveless dinner gown, long white pearl earrings, and purple high heel shoes.
In a flashback where Leni handed her bike down to Luna, who made it into a custom chopper, she wore shades, gloves, and a bike helmet with a spike sticking out like a Pickelhaube, a former German military helmet.
When Lincoln and Clyde get thrown in the mall's jail, Luna disguises herself as her mother in order to bust them out. However, Bobby easily sees through the disguise, and gets her locked up with them.
During Luna's story of how she got into rock and roll, she was a gentle and sweet girly girl. She originally had longer hair that went down to her shoulders, a girlish light purple shirt, white earrings, the same square-patterned skirt, white socks worn high and black Mary Jane shoes.
During production, Luna was originally going to dress up as Leni and do the mirror routine with her before it was changed to Luan doing so in the final version.
When the kids' grandfather called them on a video chat, Luna disguised herself as Lynn to cover for her. When their parents found out about their little charade, their punishment was to go about their tasks while still dressed as the siblings they covered. She could only jam while still dressed as Lynn, which was harder than she thought, with all the sports gear she was wearing.
Luna dresses up as a computer nerd to help Mr. Grouse prepare for an IT job interview. She wears a pair of brown dress shoes, blue jeans, brown suspenders, a white dress shirt, a red tie, a pair of purple semicircular glasses, and paper clip earrings.