Already in 1984, the movie Dreamscape had people enter other people's dream worlds, by means of a combination of technology in the sleep lab and rather obscure 'psychic' abilities of the passengers themselves. (One character learns, over the course of the film, to 'project' into others' dreams by means of pure concentration.)
Some subtle setup is going on in the dialogue before the actual trip: the protagonist mentions that the test subject (the other man whose dream he is about to join) is a steel worker; then we recognize that the projection has worked in part by the character of the setting, a construction area on top of a skyscraper. A familiar scene for a steel worker, though it's probably not something in most other people's everyday experience. The recognition is supported by a short verification dialogue after the trip back as well, when both dream subjects recall what they've experienced and it matches. (A more serious scientific verification would have both participants record their recall separately from each other, but understandably this has been contracted for the purposes of the dramatization.)
There is a rather elaborate departure sequence. The film tries to establish an authentic-looking scientific setting, drops some references to actual sleep science (such as entering REM phases), and then also visualizes the process of passage into the dream in a manner that fits descriptions of dream subjects falling asleep (such as the hypnagogic imagery, the feeling of falling through a tunnel onto the dream scene, and random sound effects). Just as all the other movies I've discussed so far (with the exception of Sherlock Jr.), there is a clear suggestion of the character being drawn into the unreal world he enters. Compared to all that, the arrival sequence is very brief — the protagonist looks around for a moment, but then is quickly absorbed in the action.
Just as before, no shifted transfer here, although we could easily imagine how it might have been staged. There could have been a shot of the scientists who monitor the sleepers, or of the sleeping characters themselves, interleaved with the dream sequence itself. Of course, there would have been little benefit to such an interruption of the dream sequence. Especially when presenting dreams, movies tend to replicate the grip they have on us in our real lives by leaving such sequences uninterrupted. (Look out for this when you next see a dream sequence in a movie: they are very rarely interleaved with any other plot elements.)
 That is, long before Inception; of course, the idea is much older. Dreamscape itself was based on a 1966 novel by Roger Zelazny entitled The Dream Master.