Can I use Intel agent to look at the dial, then use Cassion to "guess" the same maneuver? Sounds super trollie, but I like it.

No. They have different timing triggers. Cassian Andor always goes first.

Cassian Andor: At the end of the Planning phase, you may choose an enemy ship at Range 1-2. Guess aloud that ship's bearing and speed, then look at its dial. If you are correct, you may rotate your dial to another manoeuvre.

Intel Agent: At the start of the Activation phase, choose 1 enemy ship at Range 1-2. You may look at that ship's chosen manoeuvre.

Thanks. That would be broken enough that the play testers should have caught it.