For starters, here's
Cincinatti's League Park (I), home to the AA's Reds from 1884-1890 and where they remained when they joined the NL. In 1894 the park was redone/renovated, and what is the grandstand became outfield seating. So, that'll be another ballpark.
Here's a bunch of pictures and history from Digital Ballparks.
This seemed like a relatively straightforward park to make, so was the first one I tackled. Per my usual practice I'll include some historical shots along with some screenshots below. It could probably stand to have a backdrop behind the stadium so views from CF don't look so stark, but that's a problem for later me...
Google Drive Link for League Park (I) in Cincinnati