>>58197535For dub, Pokeflix is the best choice. It has almost every episode, movie, and special, including subs for episodes that were never dubbed.
The official Pokémon TV YouTube channel is decent. It has dubs other than English, but it skipped the banned episodes, has a slow release schedule currently going through late Johto, and includes all the problems that YouTube has as a platform especially when it comes to kids content which the episodes are marked as.
For sub, since there are no official releases, if you know where to look, you know. Just avoid SOSSubs for OS and AG.