>>18947437Because not all Pokemon appear on them but movie short Pokemon always appear on distribution posters. You haven't seen Hawlucha in any other movie media besides that poster for the distribution and we see it in the short. There's also nothing saying Ash will catch Hawlucha and the fact that people think the Hawlucha from the preview will be his when we already know the preview was dedicated to Korrina why the hell would the first thing to come to mind not be "It's Korina's"
See pic related or
>>18947505 