If LeBlanc plays a Reflection to Star Spring Battlefield, can she move another unit back?

No, playing a Reflection unit token using the Deceiver legend's ability does not trigger the ability of Star Spring.

Reasoning:

• Trigger Condition: The ability on Star Spring states: "The first time a player plays a non-token unit here each turn, they may move another unit they control here to its base."
• Token vs. Non-Token: The Reflection unit created by Deceiver is a unit token. Because it is a token, playing it does not satisfy the trigger condition "play a non-token unit" required by the battlefield.
• Result: Since the condition for the trigger is not met, the option to move another unit back to its base does not become available.

This interpretation is consistent with RiftJudge FAQ #10099, which addresses this exact interaction.