I tried to find some info on this power on any Star Trek site, but didn't find anything on personal cloaking devices.
It was mentioned that the Hirogen ships have a "stealth mode", whatever that means.
I'm assuming it's their version of a cloak, but it could also be a sensor masking unit making the ship undetectable, but still visible if you were to look out the window and see the Hirogen vessel directly.
That was the only information I was able to find on the Hirogen's cloaking technology.
And Romulans (as far as I know) have not developed personal cloaks, so they could not have supplied this technology to the Hirogen.
Has it ever been shown in a tv episode that the Hirogen have a personal cloaking device?
If so, can you cite the series and episode so I can see it for myself?
I submit to you that the Hirogen are basically Yautja (Predator) expy's so it stands to reason they'd have a personal cloaking shield. Now if we can only convince the designers to give them those snazzy helmets...
"In game", I think that has been in for a long time. I think a barely used Tactical Kit power does this effect as well.
But on the show? I don't remember the Hirogen well enough. I remember that another "hunter race" in DS9 where their prey, "Tosk" was capable of cloaking. And the Jem'Hardar have a personal cloaking device.
it is possible the Hirogen developed them on their own? Maybe after they learned more about the holographic technology, they build a personal device to get a cloak-like effect?