Well, the main character from
Ookiku Furikabutte blushes all the time and is incredibly awkward (though I wouldn't call him "shy": it's more like he has low self esteem), but I dunno whether the mood of the series will fit your tastes. It's seinen and sports (baseball), with a strong emphasis on the game and team dynamics and not, say, romance or daily life.
There's a hell of a lot of blushing from both sides in
Oka no Ue no Rakuen.
One of the leads in
Flat (AOGIRI Natsu) is shy, awkward, and blushy, but he's just a little kid -- I think about 6 or 7. The other male lead is 16 and awkward in his own way, but not even remotely shy and never blushes.
Planetary* -- Awkward, shy, low self esteem. Doesn't blush that much, though.
Bagjwi Sayug,
Ore no Shiranai Murakami-kun.,
Sabita Yoru Demo Koi wa Sasayaku -- Going by the first chapters, with confirmation from the category tags. I haven't read far enough to be absolutely certain, though.
And the Blushing Male Lead, Shy Male Lead, Awkward Male Lead categories should have some good titles, too.
Last edited by calstine at 5:50 am, Aug 23 2016