Yes, you can repair a cracked leather seat!
If your seats are more damaged, you can take another approach. First, clean your seats. Then, choose a repair kit that matches the seats. Next, cut off any threads hanging from the tears and glue canvas cloth under the tears.
After that, you’ll start layering the leather fillers. When the fillers reach a good level, sand them down so they’re level with the seat. Finally, clean off the seat and apply leather colorant so that the area matches the rest of the seat. Then, you can add your sealant.