Within the context of the Rick and Morty show, it is not so farfetched for the duo to cross over to any other cartoon series. However, the fact that different shows are owned by different companies who are not always keen on cross-promotions mean that an official Rick and Morty crossover is very unlikely.
The keyword here being “official.” Vulture.com recently sat own with Rick and Morty co-creators Dan Harmon and Justin Roiland. They are joined by producer Ryan Ridley and voice actors Spencer Grammer (Summer), and Sarah Chalke (Beth). The group then went on to improvise an episode of Rick and Morty done in a Spongebob-like universe.
The story of this unofficial Rick and Morty episode concerns the duo dealing with a domestic dispute between Sponge-eons, while being interrupted by guest appearances by various characters from the DC and Marvel universes. Like we said—the chances of a crossover like this happening are slim to none. Go watch it below: