And here comes the genetic phenotype trait analysis + matching populations of today.
I should mention that Yamnaya individuals that have been found and sequenced are genetically diverse, they have much heterozygosity. Their genetic traits suggest that blue eyed and dark blonde individuals are possible, curly haired and straight haired ones too. The same goes for skin color, normal Northern European light skin to mid brown was possible.
Broad faced, mesocephalic skull, narrow forehead, large eye sockets, eyes wide set, middle sized eyes.
The Nose was not extremely large or long in the horizontal position, but long in the vertical position, slim nose bridge, slim nose holes, but middle broad nostrils. The Yamnaya had a nose tip that pointed to the bottom and a hooked nose bridge. They had a prominent nose like many people imagined.
They had a long, often cleft chin and the mouth position was little more inward, the opposite trait to Africans. The mouth was of average wideness, the lips where thin. There was a little larger gap between the nose and the mouth which gave the face a longer impression at the bottom.
The skin tone was fair to light brown.
The average hair structure was wavy. The color varied between dark blonde to dark brown.
The eye color can vary between gray, unclean blue, hazel and brown eyes. There is one allele missing to get clear blue eyes, but that doesn't mean that other blue and gray tones haven't been possible. The average eye color was hazel.
Comparison with today's populations by physical traits determined by SNPs:
Middle East 80% Northern South Asian 80%
United Kingdom 77%
Estonian 76% Netherlands 76%
Danish 75% European 75% Jewish 75% Swede 75%
Bedouin 74% Palestine 74%
Sardinian 73%
Hungarian 70%
East Asian 68%
Italian 66% Orcadian 66% Russian 66%
Ukrainian 65%
Adygei 62%
Basque 61%
French 59%
Turkish 58%
They maybe looked like some Afghans, or Kalash people, but with more Northern European traits.
So the answer to the question if the Yamnaya where fair skinned, blonde and blue eyed warriors is: Yes, sometimes maybe, but not so often.