>>13419149You could do something like Elite Dangerous. In that, ships can use their made up sci fi super duper drive systems to either jump between systems through some kind of hyperspace analogue, or 'supercruise around one system at speeds approaching (or far exceeding) C. But while in supercruise ship's sensors still work, and it's possible to pick up other ships and, with the right gear, interdict them and pull them out of supercruise and force them to use their impulse engines, which operate in mere meters per second, forcing them into a dogfight.
So basically, standard giant robot fighting speed would use a separate drive from reasonable system cruising speed, but they can't fight in the latter and can potentially be pulled out of it and left exposed while the drives spool up.