Viking is just a profession or activity, not ethnicity. Slavs were participating in viking activities too. Savic vikings were called for example “chąśnicy” in case of these from western Pomeranian region of present day Poland.

It could be color marking for cardinal directions. White, Black, Red, Yellow(Golden)/Blue/Green are common conventions for marking different cardinal directions and “center” – exact order might differ between groups. You can see them in used in Kyivian Ruthenia (Black Ruthenia, White Ruthenia, Red Ruthenia), you can see them used by steppe cultures (Golden Orde and other “color” Ordes) and I found some claims that Native Americans of both Americas also used these colors.

Just like today there’s plenty of different styles. Some were bearded. Some weren’t. We can’t draw absolutes on most things back then anyways.

There’s a 2000 year old tapestry that shows a Scythian on a horse (without stirrups) and he’s clean shaven except for a GIANT handlebar mustache. No joke

https://images.app.goo.gl/e76dURHgxRVVzfLg8

If beard is fantasy why all sculptures and engraving showing viking man with beard?

It is not quite truth. Longer hair was wanted under helmets, they worked as layer of protection and also it is much more confortable to wear it. Just try one of these steel medieval helmets. When fighter was not rich enough to have helmet, no hair was prefered as you said.

I believe I read once it was either due to the nature of their presence with the ‘white Danes’ being traders and the ‘black Danes’ being invaders or that it was the predominate hair colour of the respective ‘Danes’ with blonde being white and dark hair being black. Specifically that those from Norway were more likely dark haired and those from other parts of Scandinavia being more likely to be blonde. Probably more nuance to it though.

There is evidence suggesting otherwise. On Gotlandic picture stones, men and warriors are pictured with pointy chins suggesting beards. There are also beards on male figurines from the viking age in Scandinavia and Iceland as well as on wood carvings on the Oseberg ship.

Why were the Danes called “Black”? Is this a joke?