Keyword collections would be faster than renaming the clips. When importing, have that collection highlighted, and they’ll import directly into that collection. If you right-click the Browser headings (in List mode) and select to show Video Frame Rate, you can then sort them by FPS. Select all of those clips at once, drag them into the collection. Too bad Smart collections don’t have a Video Frame Rate option.
Where are you seeing that FPS? In the Browser column?