Hi Minu,
We’ve had a few other similar projects shared on our forum, there are some helpful insights there:
Rotating a thruster while it is running is particularly tough on both the thruster and the servo, due to the gyroscopic action of the rotating mass. Both the T100 and T200 are now toughened up in the necessary areas, and should handle this fine. A fair bit of torque is a good idea here to keep the servo from being over stressed, and a waterproof servo is nice so splashes are not a worry. The HS-5646WP should do well. Note that a decicated high current BEC is strongly recommended, as these servos can draw more current than the 500mA BasicESC BEC can provide.
-Adam