I don't think it's a matter of challenge, according to many leaks and news about the coming S26 Ultra denotes that Samsung is going to use Sony sensor on its new phone
The mobile photography world is heating up as Sony prepares to challenge Samsung's dominance in ultra-high-resolution sensors. Reports confirm the upcoming Sony LYT-910 is the company's first 200MP phone camera sensor, featuring a large 1/1.11-inch size. Check its key leaked specs here.