The official Pokémon movie website has updated. Translations follow:

"In Celebration of "Mewtwo Strikes Back Evolution"'s Premiere! "Pocket Monsters the Movie: I Choose You!"", the Tv Special Airing Saturday July 6th, Will be Streamed Online for Free!

"Pocket Monsters the Movie: I Choose You",
which will air on TV Tokyo Saturday July 6th at 12:30pm,
will also be streamed online in real time!

It will be streamed on these 4 services:

*Twitter (Periscope))
Streaming account: The official Pokémon movie Twitter account (@pokemon_movie)

*AbemaTV
Streaming channel: Abema Anime Channel
https://abe.ma/2YydsOC

*LINE LIVE
Streaming account: Toho
https://live.line.me/channels/51648

*Tv Tokyo's official streaming service "AniTV"
https://ch.ani.tv/

Let's enjoy the "TV Tokyo Pokémon Festival" all across Japan!
Both on TV Tokyo and on the Internet!

The stream will start Saturday July 6th at 12:30, the same time the TV broadcast starts,
so don't miss it!

Source: https://www.pokemon-movie.jp/news/?p=3740