Yeah the number of individuals who could do this…
…probably number less than 100 in the entire history of Star Wars. But they exist. And depending on which time period you go with there’s either thousands if not millions of Jedi/Sith - each one pound for pound either is worth an entire squad up to an entire army unto themselves - or have to deal with a dozen doomsday stations per square kilometer.
Then there’s the fact that as ME 3 showed the Reaper’s biggest asset was their ability to divide and conquer. They shut down Mass Relays to cut of systems from each other and then pick them off one by one. They still have the numbers to attack an entire galaxy, but it meant them taking heavy losses since they couldn’t just dogpile their targets anymore. In Star Wars every ship has a hyperspace drive, one that I think lets you travel faster than a Mass Relay would no less. That level of mobility is a gamebreaker.
Honestly the only real 2 strengths the Reapers could bring to bear against Star Wars is A) Their numbers and B) Indoctrination.
With the former, again, they can siege an entire galaxy with one unified force. But Star Wars is no stranger to galaxy spanning armies; shoot, get the Separatist factories back up in running or bring the Empire’s resources to bear and they can meet those numbers. Or even the Star Forge to let one guy meet those numbers.
Indoctrination comes in 2 flavors though. If the Reapers hit them with the fast variety (RE:done over a few hours, perhaps in a battlefied) then they are left with brain addled puppets useless for anything but turning into husks. If they can sneak one of their techs into a major population center or government then they could brainwash the leaders over the course of weeks/months. But depending on the type of government that would only work up until the leader gets ousted for treason, and due to the factionalization of Star Wars’ many different races would only work for that particular group.