If you look just at project plans in Clarity they do not offer scenario or version functionality. Just one current version. Then there are the baseline. I do not know if they offer the options for dependencies you need. The do offer the options for different durations and work efforts. Neither do I know if it is possible easily to switch a given baseline to be the current plan.
As said in LinkedIn with OWB you can any number of versions or scenarios if you save them to files. You can copy e complete version over the current plan and thus save that into Clarity.
Portfolios also have scenarios or plans in the newer versions, but even if that worked the way you need to me it sounds impractical to have a portfolio for just a single project. That would add over head and include more rights to manage at project instance level.