But no other episode with BOTH cross dimension and time travel? IE: the time travel creating parallel worlds?
Good question. I don't think so. Alternate universes are a thing in the Star Trek universe and so is time travel, but I can't recall any episodes which explicitly combine them. But let's look at how time travel works in Trek.
The Trek universe is paradox-tolerant, ie you *can* go back in time and disintegrate your grandfather with a phaser. The timeline will change, but you won't be wiped from existence. You'll just be a logical impossibility (hopefully with a guilty conscience, because you committed murder to prove a point about time travel paradoxes).
The best example of this is in "City on the Edge of Forever". Drug-addled McCoy jumps into the Guardian of Forever, travels to 1930s Earth, and
changes the past. The Enterprise is gone from orbit. Yet the away team is
still on the surface, and McCoy is still in 1930s. How did they get there? Were any of them even born? Welcome to Paradoxville. Please enjoy your stay, and refrain from killing you distant ancestors.
The Trek universe also strongly suggests that each universe has a single "correct" timeline. A good example of this is "Yesterday's Enterprise" (TNG). The Enterprise-D encounters a time-hole (err, temporal anomaly), and out pops her predecessor, the Enterprise-C. In flash the timelines changes. Suddenly the Enterprise is a full-on warship, and the Federation is losing a long war with the Klingons.
Fortunately for the plot, Guinan the mystic space bartender remembers the "correct" timeline, and convinces Picard to send the Enterprise-C back through the time-hole (to it's certain destruction) which restores the "proper" history.
Time travel in Trek is also ridiculously easy to do. By the time of TOS, every warp-capable starship can double as a time machine, via the warp-slingshot maneuver. During TNG, Picard and Co. meet a 22 century con-artist with a more traditional 26th century time machine. In DS9, the crew travels back the TOS episode "The Trouble With Tribbles", and runs afoul of the Starfleet Time Travel Police -- who exist, apparently, because the Federation has something of a time-travel problem. By the time we get to Voyager, we meet Federation people from the 28th or 29th century who fly around in "timeships", ie by then, the Federation has a fleet of nacelled TARDISes.
Then Enterpise introduces the "Temporal Cold War", which made things even more confusing.
Put this all together and you see time travel in the Star Trek universe has always been a huge honking mess -- long before the writers of Trek 2009 came on the scene.
Sorry, but words have meaning. Grammar has rules.
Which change over time. Always. Trust me on this, I DM for a PhD in linguistics!
I mean, what does the word 'phone' (n.) mean? Is it the rotary telephone on a table from my youth... or the computer with a touchscreen interface connected to a global data network which also can make telephone calls? The answer of course is *both* are phones -- the definition of the word now includes fancy pocket-computers.