Truth about Graphene:
Graphene is nothing more than a one-atom-thick layer of carbon atoms arranged in a certain pattern. That's it.
Graphene has some amazing properties and it's being researched for all kinds of possible uses.
It is thought to be an anti-viral and anti-bacterial substance because it works like diatomaceous earth on a smaller level ... with its shaper edges hacking up microbe-sized particles (just as diatomaceous earth does to insects with chitin shells).
There's some concern that it can damage human cells also ... in larger quantities. But the body can actually expel graphene (unlike, say, asbestos).
There was some graphene found on some of those blue paper masks ... probably with the intent of serving as an anti-microbial. But it's not known whether it could damage human lung tissue in small quantities, so some governments have banned them. It's probably wise to avoid the blue paper masks. Most of them do not have this property, because they're manufactured by slave and child labor in India and China, but the cheap ones manufactured there will not have graphene because it would cost too much (graphene is somewhat difficult and expensive to make). Nevertheless, there have been videos shown of these blue masks being made in unsanitary conditions. So, overall, I would avoid them.
Now, here's where the conspiracy theory conflation beings. Because of its amazing properties, graphene is being researched for all kinds of uses, particularly with regard to computers and electronics, and it has in fact even been used as a coating on some nanobots. Nevertheless, GRAPHENE ITSELF IS NOT A NANOBOT. It can be used to make nanobots, but is not itself a nanobot.
So the conspiracy kooks find an article or two where graphene was used to make a nanobot, and therefore draw the conclusion that the graphene found on masks and swabs are in fact nanobots, when in fact, there's no proof of any of this. Graphene has been found, not graphene-based-nanobots.
So, no, getting a few particles of graphene from a swab or a mask will not turn people into mind-controlled zombie robots who will be controlled by 5G.