Depending on how often you plan on doing this, I can think of a few ways to go although none of them are as simple as layers:
One possible workaround would be to make a copy of the clips in question and paste them on lower tracks and disable the A/V checkboxes on the left end. Disable all of the effects there so you'll have a "clean" copy, but you won't ever risk losing your original changes. You'd need to disable the checkmarks for the main track(s) and enable them on the "clean" one(s) to preview them.
An alternate version would be to paste them in a new project, which you can even insert at the end of your main project and not have to worry about enabling/disabling tracks.
Another idea would be to produce the original timeline and keep a copy in the media library (or disabled on the timeline).
All of these would be appropriate if your timeline content is basically set and you're mostly looking to compare your recent additions to it. You'd have to make a new copy or make the same changes to your existing copy every time you made a content change, which would probably be a lot more work.
Finally, don't forget about project saving and the Undo function. Both of those will protect you from losing things like Color Match which gets reset if you uncheck the box.
YouTube/optodata
DS365 | Win11 Pro | Ryzen 9 3950X | RTX 4070 Ti | 32GB RAM | 10TB SSDs | 5K+4K HDR monitors
Canon Vixia GX10 (4K 60p) | HF G30 (HD 60p) | Yi Action+ 4K | 360Fly 4K 360°