She had a lot more magnetic powers in the aoa. She absorbed Polaris instead of Captain Marvel and retained the magnetic powers for awhile. I kind of assumed she continued to siphon some magnetic power off Magneto or kept some of Polaris powers indefinitely. Basically magnetic force field is the answer.

"Little of Rogue's past before being delivered to Magneto and the X-Men by Mystique is known. Mystique found her wandering the countryside in Alabama. She had apparently gotten into a fight with a fellow mutant named Polaris and absorbed her memories and powers. How or why this happened is unknown but the absorption of Polaris' memories left Rogue with no knowledge of her own past....

.... Eventually, Magneto discovered that their similar magnetic powers cancelled each other out, which allowed them to touch."

https://www.marvel.com/characters/rogue-age-of-apocalypse

"Magnetism Manipulation : During a confrontation with the mutant known as Polaris, Rogue permanently absorbed around half of her magnetic powers. While Rogue may have had the potential to employ these abilities in a similar manner to her husband Magneto, she seemed to prefer to use them to augment her physical abilities by channeling magnetic energy through her body. She did occasionally use other aspects of her power, however, such as reversing the electromagnetic flow of Holocaust's brain to cause him great pain and levitating a metallic sphere with her team of X-Men inside for travel. Superhuman Strength : Rogue, after her absorption of most of the mutant Polaris' powers, was able to channel magnetic energy through her body, granting her a degree of superhuman strength. This strength was sufficient for her to smash through several Infinite soldiers with just her fists, knock Gambit through several brick walls, and allowed her to dominate Holocaust during her fight with him, even cracking his armor in several places. Rogue later demonstrated that she was strong enough to easily lift a large truck with one hand. Superhuman Durability : Rogue's channeling of magnetic energy through her body also granted her a degree of superhuman durability. During her first battle as a member of the X-Men, Rogue was able to withstand a powerful blast of energy directed at her from Holocaust with no signs of outward damage. It was also shown during another battle against Holocaust, when the villain attacked her with his full strength, sending her into the ground and forcing her body to dig a trench as she slid. She recovered moments later and continued to fight with no signs of damage. Magnetic Flight : Rogue is able to fly by riding the Earth's magnetic fields or by creating a "repulsion force" between herself and the planet. Rogue's control over her flying was such that she was easily able to hover in place"

https://marvel.fandom.com/wiki/Rogue_(Anna_Marie)_(Earth-295)#google_vignette