Crop video in ffmpeg without re-encoding
A videofilter in ffmpeg always has to modify pixel information hence the reason why you need to re-encode.
It seems logical at first that you wouldn't have to do this when cropping but the way lossy video codecs work makes this pretty impossible without re-encoding everything.
They usually don't see an array of pixel information but a much more complex representation of pixel blobs that are described in a way that takes up less space than the original pixel blob, you can't really "crop" that encoding, to do a crop you would first need to decode the information to know what you are dealing with but then you need to re-encode to have it compressed again. Thats the main stepping stone.
Then they also use things like motion estimation that depends on information before and after certain frames, if that information changes all of the sudden the whole thing is screwed up and you end up with tons of artifacts when decoding the video during playback.

tldr; no its not possible to crop without re-encoding in any tool.

Unless you deal with some very specific lossless non-consumer intermediate codecs that would enable it but in that case transcoding wouldn't be an issue.