It is claimed that blue-krypto removes powers. Turns out it inverts their powers.
The red sun removed Clarks powers and gave the rest theirs back. The blue-shard would have removed the bottled Kandorians powers if they were exposed to its radiation during the red-sun.
When the sun turned yellow, chick-assassin was holding onto the crystal, allowing her to retain her powers when Zod lost his. Back in the past, by not being in direct contact with the blue crystal, she lost her powers and the radiation subdued Clark's.