I'm at the Japan expo in France and the premiere just ended (I'm French so sorry for bad English)
There isn't a teaser for the next movie or anything at the end (like there was at the 18 film with perfect zygarde)
The movie features a lot of moments of the first season, ash only catch Caterpie and Charmander (the Charmander was abandoned by the guy with the incineroar who only wants to have powerful Pokemon and don't give a shit about friendship).
If you have questions feel free to ask I will try to answer