If they're not a fixed location or fixed orbit or ancient alien gate that would go a long ways to avoiding the problem.

Actually, fixed location worm holes that don't move relative to stars might be interesting too, though I think one of the ramifications would be that they're almost always out in deep space.

Brings in other questions.

If they orbit as part of a system, is it because of orbital mechanics? If they're artificial, do they have a fixed location relative to the star, or relative to a combination of points.

FINE. I won't sleep tonight.

An artificial gate like the ones in Fading Suns have mass and orbit but naturally occurring wormholes might be like eddies and swirls in a stream but caused by gravity waves.  That would give them an orbit like spin.  Alternately the wormholes might be caused by micro black holes with the mass of a planet.  Worm holes caused by gravitic stresses due to orbital alignments might open and close as a result of planetary motion.  Of course, if they have their own trajectories independent of gravitational effects the stellar motion might be slow enough that they only move very slowly relative to the star system.  Wormholes caused by implosion devices might have their own trajectory or simply be static relative to the universe's expansion.

The Frontier Canon is that these wormholes are utterly undetectable without a "Keyhole" drive. The thing that opens it up. It's believed these wormholes are finite (not true) and pre-engineered (that's only partially true). Human Unity has spent decades mapping existing wormholes, looking for essentially "side passages" in 4-dimensions which could open up other routes. Until then we can only deal in the exchange of routes from a much more advanced race whose barter system often leaves us without a clue....

The wormholes we know about are tied to systems. Others....well....

The theory is that the Keyhole Drive, which is essentially a black box, opens up a different 3d topographical layer of space (like the network of tunnels in an ant colony under a lawn, but in fully 4 dimensional space). I don't mind having a bit of handwavium...