Achievement Unlocked: Wire a box with 6 different wire functions without using any phase tape
Sorry, no points for that "achievement", just a lot of brain pain. Let's try this.
Ah, suddenly I can hear myself think
Most of this looks pretty straight forward. The top /3 cable is the supply side of a 3-way circuit. The bottom /3 cable supplies light and fan in the usual manner.
But something rather squirreley is going on with cables 2 and 3 here. You've labeled cable #3 as "Line" but then, feeding all the switches off the black wire of cable 2 doesn't make any sense.
So this raises more questions than answers.
What might make more sense is if cable 2 was actually line, and comprised a multi-wire branch circuit, with one pole serving all loads here, and the other pole heading off to parts unknown in cable 3. Does the breaker for this circuit have 2 handles and the handles are tied? (on Square D "QO" this might look like a double-wide breaker with a single handle).