is a recent visual novel that apparently has some foot-related eroge, and it actually looks like a rather good read, though since it's new it may be a while before it gets a translation.
is a VN currently under translation that has a foot focus in an apparently similar way to the above, but this one's got more and better votes. Of course, I haven't played either of these so I wouldn't know.
If you want non-sexual Foot Focus
, then I wouldn't know where to go. It's not really a common thing in visual novels, really, for whatever reasons. Sometimes you can just pretend that the characters have nothing below their waists except in ero scenes.