It looks like this functionality is finally available if you enable the "#memory-saver" advanced flag in Opera. Once you enable this flag and restart, you will have a performance section with the memory saver options in the settings area just like Chrome does. I enabled and it seems to work similar to Chrome. Additionally, I found out if you pin a tab, it won't snooze the tab. This is exactly the behavior I was hoping for. So with "#memory-saver" flag enabled and turning on the memory saver in the opera settings it makes for a much better experience when you have lots of tabs open in the browser. Happy to see this finally became available in Opera.
