Just been playing my first large map with several star systems so didn't have this problem before, this may be a stupid question but...

How do I force ships to jump using the star route? There's a wormhole connecting the two star systems and the ships always chooses that route, but it's a heavily trafficated node which makes it impossible to sneak past single ships or small fleets. I also have a phase stabilizer in a newly conquered planet in that star system, but yet again, ships choose the wormhole, do phase stabilizers only work within the same star?

I should mention it doesn't matter if I put the ships in the same gravity well as the star or a planet with another phase stabilizer, they still take the wormhole.

Is there any solution to this?