Here are two instances of official products that allow this sort of travel:
The D&D Basic product, AC4: The Book of Marvelous Magic by Frank Mentzer had an appendix that allowed direct adaptation its contents to AD&D 1e, so it was advertised as compatible with two different versions of Dungeons of Dragons. In this sourcebook, a couple of magical items called 'Alternate World Gates' were defined. These items are just regular items of their own worlds (like a laser pistol from the Gamma World), but would be odd in others. When the item is touched, it summons a character from the alternate world, who comes from a gate, grabs the item and leaves. If the characters react fast, they can jump through the gate themselves and arrive in the alternate gaming world. A 'dirk of avenger summoning' allowed AD&D characters to travel to D&D basic, and a 'lute of bard summoning' allowed D&D basic characters to travel to AD&D. Other items allowed travel to Top Secret, Gamma World, Dawn Patrol, Star Frontiers, Boot Hill and Gangbusters.
The second example is through time travel. In principle, one could argue that time travellers should be able to visit different D&D editions, motivated by the fact that the edition transitions were coupled to various major in-game events described in novels and adventure modules, such as Fate of Istus, Avatar Trilogy (Shadowdale, Tantras, Waterdeep), Die Vecna Die!, etc. We have instances of time travelling in the Forgotten Realms Arcane Age series of products, such as the Netheril: Empire of Magic boxed set. In these products, characters were given the possibility of travelling back to a historical period when the mechanics of spellcasting (and a number of other game characteristics) were very different from the default in AD&D 2e. Of particular interest for our question, we can consider the adventure module How the Mighty Are Fallen, which allows characters to experience the event known as Karsus's Folly. In the prologue, we even get a clear statement:
For DMs who desire to be historically accurate, game play reverts to strict original AD&D rules (not 2nd Edition). This means that clerics and druids are two separate classes, as are mages and illusionists. Specialty priests and specialist wizards no longer exist.
So you could officially time travel with the AD&D 2e time conduit spell to the Arcane Age with its own "semi-edition", then live through Karsus's Fall and naturally move to AD&D 1e. Then the conclusion of the 1-year duration of the time conduit would pull you back to 'your own time' in 2e.
PS: An appendix to the 2nd edition accessory Chronomancer discusses a means of allowing time-travelling AD&D characters to interact with those of the Gamma World game. Quoting from the updated and expanded version of this appendix that is available for free from the WotC:
It is possible that a far-future group of technological time travelers will be created in an alternate future to patrol Earth's history as a sort of "time police." If encountered, these officers could be easily designed using materials from the GAMMA WORLD(R) game ... . The GAMMA WORLD game itself could depict an alternate future of Earth; this system is largely compatible with the AD&D game. A few mutant humans or animals might have the Time Field Manipulation mutation and thus meet up with actual chronomancers (see the GAMMA WORLD 1st Edition game (1978), page 14).
It is interesting to note that at the time of Chronomancer's publication (1996), Gamma World was already in its 4th edition (1992), which is supposed to be like AD&D 2e, while the quote mentions the much earlier first edition.