There are different grades of reflectivity, the kind that is common for vehicles and print is engineer grade / glass beads. It is the lower end of the reflectivity brightness wise.
That being said Nikolai does make a high intensity glass bead that is printable, but for whatever reason they put star watermarks all throughout it.
My guess is that Op wants to use a prismatic reflective, like 3m 3930. It's mainly used in traffic signage but it reflects way better than regular reflective vinyl and captures light at much wider angles.
If it is for traffic, you can't just print it with any printer. Heck, even though it is latex compatible you can't just print it with a compatible printer, you have to get your machine certified for traffic and use actual traffic software to make sure that the colors fall within spec.
You can cheat and just use a latex, but as soon as somebody crashes around the sign and investigates whether the sign is up to code, guess who is liable if it is not?
So if it's for traffic I would stay away. If it's not print on an optically clear over lamb and apply it on top if you don't have the proper inks. You will lose some of the reflectivity but it's pretty much the only way. We used to do it for real estate signs and it always turned out nice.