I don't know if cooters and sliders can produce viable offspring, and we can't see enough of the animals to give a good guess. I'm going to alert one of our more knowledgeable water turtle guys - @Markw84
I have not seen a cooter (Pseudemys) slider (Trachemys) hybrid. It may be possible as Trachemys used to be part of Pseudemys and more recently split into their own genus.
I also don't see any cooter influence in the looks of the turtles you are showing. They look pretty classic slider to me. A hybrid would have a much more washed out plastron pattern as well as different head and neck striping. The red stripe is always much more washed out in any hybrid I have seen of just slider/slider hybrids and would imagine much more so if it were a cooter/slider.