iFixit just released some disassembly instructions and replacement parts from their website. It looks to me that the Kobo Libra Color and the Kobo Clara Color does not have an SD card slot.
Link to Kobo Clara Color Motherboard:
https://www.ifixit.com/products/kobo...rboard-genuine
Link to Kobo Libra Color Motherboard:
https://www.ifixit.com/products/kobo...rboard-genuine