One such timeline was explored in an issue of Rather than beat the demonic invasion, the majority of the X-Men are killed when the demon S'ym absorbs the energy from fellow demon N'astirh.

Source: https://www.cbr.com/xmen-characters-corrupted-others/

She might suspect that Belasco has no intention of helping them, and recognizing that S'ym does owe them, she gives him the sword in exchange for his help.

Source: https://www.cbr.com/black-cat-mary-jane-spider-man-sacrifice-marvel/