There were a couple episodes that I found really cool but guess what, it's like when a tv show purposefully annoys the viewers but leaving a cliffhanger. So, were any of the episodes ever continued somewhere? If yes then where?
Pokémon Generations (ポケモンジェネレーションズ, Pokemon Jenerēshonzu) is a Japanese-animated original net animation series produced by OLM and released on YouTube by The Pokémon Company. Similar to the 2013 anime television film, Pokémon Origins, the series consists of several short stories inspired by Nintendo's Pokémon video game series (from Generations I to VI), as opposed to its main television series. A total of 18 episodes were produced, and were originally released in English on YouTube between September 16, 2016 and December 23, 2016.[2] Japanese episodes have also aired via YouTube.
Source According to Wikipedia, there have been only 18 episodes released, and 3 episodes for each generation. And as you asked, the 15th episode have been never continued.
Hope this helps!
Pokémon Generations Series only contains 18 episodes and 6 gens.
Each gen had 3 episodes.
The series ended with generation 6 and no more episodes has been released.