Changing Timebase Without Re-Rendering?

I have a ton of 60FPS APR (Apple Pro Res) 422 files. I want to package it at 24FPS. I don't want to conform to 24 FPS because I don't want to lose those frames. I want to interpret that footage at 24FPS so it playback slower. Easy. Seems to me I shouldn't need to re-render everything in order to make this change. Seems like an adjustment to the time base of a file is an under the hood solve. If I remember correctly, long ago, you could do this with something like compressor.