Looking for recommendations for yaoi where the classic blushing, nervous personality actually belongs to the seme instead of the uke or reversible. Ideally it could have an actual plot too.

The title story from Doutei Hitsuji to Abazure Ookami (first 2 chapters + end-of-volume extra), definitely. It doesn't have much of a plot, but it's really adorable, imo.

Negai Kanae Tamae - The seme is actually a fairly normal guy; he just seems uke-like compared to the actual uke, who's extremely manly. The best thing is that this has an actual plot!

Scratch Blue
Wazato Janakute mo Gomennasai
First story from Sono Koi, Seiritsu Naru ka
Zenryaku Love Hotel yori
The first and third stories in Retsujou.
Waraibanashi no You da

There's also the Uke-like Seme and Crybaby Seme category tags, though I can't vouch for all the titles mentioned.