Not an aircraft I have worked with, but in addition to the swing rate being slowed by controlling the hydraulic supply, the left side side brace seems to have actuated first and the right side side brace didn't move until the left gear began to "climb the hill" into the wheel well thus increasing pressure enough to move the right side brace. Once the right side gear began to move, they both seem to have come up pretty evenly.
As previously stated by others, the gear is being actuated with much lower than normal flight hydraulic flow rates/ pressures to make it easy to visualize the sequencing of the retraction.