LR Develop module has “snap-shot” capability, sort of.
Click [Add] in the History pallet and it combines all previous adjustments into one time stamped develop-state (snap-shot). Clumsy compared to RSP, but you can save different develop states. It would be so easy to simply put snap-shot buttons across the top of the image window like RSP. Having to open the left side Presets/History panel is a pain and v inelegant.