Doraemon Movie 26: Nobita no Kyouryuu 2006

If you want a movie-lenght feature condensing what's good about the more "isekai"-esque aspect from Digimon (the characters going to a place different from reality where they get their views of the world challenged), look no further than this movie, which is a remake of a 1980s film made long before the monster fighting franchise (and even before E.T., the classic unusual pet hollywood movie). I choose Digimon Tamers from all the series in the franchise to make the best comparison because both the Doraemon movie and that Digimon series -First spend a reasonable amount of time in the real world, letting us know the characters with more detail (unlike Digimon Adventure 1999, which starts almost exclusively in the otherwordly realm), placing a great emphasis and drama in hiding the creatures as they could end up in hands of the authorities. -When they do go to the place away from our own current reality (the dinosaur times in Doraemon, the Digiworld in Tamers), they do so in aid of a creature they became friends with (Piisuke in Doraemon, Culumon in Tamers). -They can't go back to their own place so easily, both works becoming a road adventure to reach a certain destination (Unlike Adventure 02, in which the kids go back and forth at their will, eliminating the stress factor), all the while the characthers change: Doraemon is more optimistic in their development and reaffirming of their friendships (like in Digimon Adventure), while Tamers gets a really cynical plot twist for one of their main leads and more complex questions about the legitimacy of their friendships. -During their travel, they are both chased by forces that overpower them, as they still are vulnerable kids: In Doraemon, they are chased by psychotic poachers who want the dinosaur for themselves, and in Tamers, the kids are chased by servants of a god who want them dead, for much more complex motives regarding cybernetic existentialism. -As in Adventure and Tamers, the Doraemon movie has an extremely heartwarming but tearjerking ending where the protagonists must say goodbye to the creatures they spent so much time together with, though the Doraemon movie's reveal is a logical conclusion the viewer can prepare for and shows the things the main lead has learnt throughout the journey, while those Digimon series' reveals come out of nowhere at the last second, making them more shocking than characther developing (you can consider it a spoiler, but I assure you the finale hits harder knowing what's coming). The Doraemon is ultimately a lighter take on the structure, while Tamers is the more complex but often contrived take on it. I recommend both, though I may remark that Nobita's Dinosaur is a two halves film which ends right after the protagonists come back from the past, while Digimon Tamers has a three act structure that shows as a last third the consequences and after effects of the kids having adventured into the "isekai" place, facing both trauma and a colossal threat, which makes, in my opinion, the best part of the show. read more 

I just imagined the same dinosaur & there's farewell story too.. ^_^