>>50565147Watch OS because it establishes the formula and is pretty funny, referenced a lot later. Skip most of Johto
Watch the beginning of AG and the League. Watch all of the Battle Frontier.
Watch all of DP (skipping filler as you like)
Skip BW
Watch all of XY (skipping filler as you like)
Watching SM is up to your preference, if you like the more slice of life/comedy vibes with the family theme, go right ahead, you'll have a great time. Regardless, watch the beginning of SM and the league, I wouldn't skip that league for the world.
Watch PM because it's meant to be the culmination of the previous series.
Oh, also, watch all the movies up until DP. BW and beyond aren't really worth it unless you like Legendaries: The Movie with the Hoopa movie.
Watch the Diancie movie if you like cute princesses 