I've got a ruleset called Starmada that includes a Newtonian movement system - its mostly based around a table that takes into account your vector change and speed change, and converts it into how many movement points it would take to do so. But, yes, it is a Hex-based system.
Excuse me if I'm wrong, having only read the novels rather than played the game, but isn't the Starfire drive system somewhat inertialess? In effect, it allows movement that takes mass into account but not fully so ships can maneuver in ways more like the "banking" moves of aircraft, just at speeds determined by their size?
That said, with the scale of space wargames, one has to wonder - does the movement system already take thrust vectoring and newtonian movement into effect? The distances that the battles are fought at, and the ship's speed, its certainly got to be a question of whether the movement system is abstract enough to allow for that.
To some extent, Full Thrust does that - while the Normal Space Drive ( NSD) allows for movement that isn't strictly real-world, it is based on the Newtonian principle of motion continuing unless acted upon ( Using thrust to speed up, slow down, or change direction ), and the inertia of larger ships being harder to overcome for such changes. So in effect, you
could say the result on the table of the motion is the sum total of lots of tiny course adjustments that the scale of distance makes too fine to see.
At least, I'm willing to accept it