On October 29th, 2021, the official Japanese Twitter account reminded people that this episode was available to watch on the official Japanese YouTube channel. The video was region locked to Japan only. It was available from October 29th, 2021 to November 5th, 2021. This episode was specifically labeled as a limited time broadcast (期間限定配信).

Pocket Monsters Anime Episode 85 'Rival Showdown! Satoshi VS Saito!!'
What did you think!?
Incidentally, Go was imitating Saito during the sweets time before the match...
It was surprisingly similar.

アニメ「ポケットモンスター」第85話「ライバル決戦！サトシVSサイトウ！！」 いかがでしたか⁉ ちなみに、対戦前のスイーツタイムでゴウがサイトウの真似をしていましたが… 意外と(!?)似ていましたね

The official Japanese Anime PR Twitter account posted an After Story comic on October 31st, 2021 by #もじゃクッキー @mojacookie.

Anipoke Episode 85 After Story
Just before the start of the battle between Satoshi and Saito,
Korni made an unexpected request to Go in the audience.

アニポケ 第85話アフターストーリー
サトシVSサイトウのバトル開始直前、
観客席でコルニがゴウにまさかのリクエスト

Korni: Do one more copy of Saito.
コルニ: サイトウちやんの真似、 もぅ一回やつて
Go: Huh!? (へっ！？)

CoroCoro Comic's Official website posted an article about this episode just before the original airing on October 29th, 2021. They also tweeted about the page on the official CoroCoro Comic Twitter account to promote it which the official Japanese Anime PR Twitter account retweeted.

It's almost time for Anipoke! The third fight till the end! Satoshi VS Saito!


The anime "Pocket Monsters" will start airing soon! It airs every Friday at 6:55 p.m. and it is very popular! In this article, we'll introduce you to the Pokémon and characters that will appear in today's episode, as well as comments from the voice actors and director, and other Anipoke information you won't find anywhere else! Today's episode is all about battles! Pokémon is all about battles!


Satoshi has made it to the Hyper Class in the Pokémon World Championships. His next opponent will be his rival, Saito, with whom he has fought two fierce battles with in the past!　Satoshi and Go head to the Lateral Stadium to check out the battle site... and there they find their opponent for tomorrow, Saito!


▲ Satoshi and Go saw Saito, who was training hard for the battle.


▲ Satoshi and Saito show each other their Pokémon and pledge to fight hard!

On the day of the battle, Satoshi is on his way to the stadium with a Mega Glove on his hand that shines with the Keystone!　Satoshi has fought Saito twice before, but lost the first match and had a draw on the second, so he's never beaten her before.


▲ Satoshi's current rank is 64th in the Hyper Class. He's got plenty of fighting spirit!


▲ Satoshi got the Lucarionite on Mega Island. Is he going to Mega Evolve?

Saito, on the other hand, is his opponent who strives to become stronger every day!　

And on Saito's hand is the Dynamax Band!　

The fatal battle between Mega Evolution and Gigantamax is about to begin!


▲ Saito is ranked 30th in the Hyper Class. There is no shortage of opponents!

The battle will finally start at 18:55! Let's watch this fierce battle in real time for sure!


▲ Before, Lucario fought with the mighty Otosupas to the bitter end. Now that it's evolved, I'm sure it can do it!


▲ Saito's trump card, the Kairiky, finally makes an appearance! How will Satoshi attack it?


▲ This time it's a 3v3 battle! Watch out for the Pokémon they'll unleash!

【アニポケまであとちょっと！】3度目の死闘！ サトシvsサイトウ!!
毎週金曜よる6時55分から大好評放送中！
アニメ「ポケットモンスター」まもなく放送スタート！
この記事はアニメ放送直前に、今日の放送回に登場するポケモンやキャラクターの紹介、声優さんや監督からのコメントなどなど、ほかでは聞けないアニポケ情報をお届けするコーナーだ！　今日はがっつりバトル回！　ポケモンはやっぱりバトルだぜ！
『ポケモンワールドチャンピオンシップス』でハイパークラスまで上り詰めたサトシ。次の相手は、過去2度にわたって激闘を繰り広げたライバル・サイトウだ！　決戦の日を明日にひかえたサトシとゴウはバトル会場の下見にラテラルスタジアムへ向かうと…そこには明日の決戦の相手・サイトウの姿が!!
▲サトシとゴウが目にしたのは決戦に向けて鍛錬を欠かさないサイトウの姿。
▲お互いの手持ちポケモンを公開し、健闘を誓いあうサトシとサイトウ！
そしてバトル当日、スタジアムへ向かうサトシの手にはキーストーンが輝くメガグローブが！　サイトウとはかつて2度戦ったが初戦は敗れ2戦目は引き分けと、サトシがまだ一度も勝っていない相手だけに絶対に負けられない！
▲サトシの現在の順位はハイパークラスの64位。気合は十分のようだ！
▲メガ島でルカリオナイトを手に入れたサトシ。出るのかメガシンカ!!?
一方のサイトウは日々強くなるために努力をつむまさに宿敵！　
そしてサイトウの手にはダイマックスバンドが！　
メガシンカvsキョダイマックス、運命のバトルがいま始まる!!
▲ハイパークラス30位のサイトウ。相手にとって不足なし!!
いよいよこのあと18時55分からバトルスタート！
この激闘は…絶対にリアルタイムで観戦しよう！
▲以前は強敵オトスパスと五分の戦いを見せたルカリオ。進化した今ならきっと!!
▲サイトウの切り札・カイリキーがついに登場！　サトシはどう攻略する!?
▲今回は3vs3のバトル！　2人が繰り出すポケモンにも大注目だぞ！

From June 24th, 2022 until July 8th, 2022, 10 episodes selected based on Satoshi's World Championships battles were available on the official Pokémon YouTube channel. They were available for a limited time and were region locked to Japan.

Episodes Available:
18 - Satoshi Joins In! The Pokémon World Championships!!
51 - The Great Kamonegi Trial!
60 - Aim to Become Leek Master! Stay With Me, Chivalry!!
65 - Dragon Battle! Satoshi VS Iris!!
77 - A Super-Electromagnetic Hyper Class Battle!
85 - Rival Showdown! Satoshi VS Saito!!
86 - Mega Evolution VS Kyodaimax
99 - Marie from Spiketown!
104 - Hyper Class! VS Elite Four Dracaena!!
109 - VS Kibana! A Fight with Masters Eight on the Line!!

Source: https://twitter.com/anipoke_PR/status/1540258429293383680 and https://www.pokemon.co.jp/info/2022/06/220624_a02.html

The official Japanese Anime PR Twitter account posted a behind-the-scenes look at the making of this Anipoke episode with a production artwork piece on October 28th, 2021. The picture featured Saito's Kairiky.

Kairiky, Pikachu, and Sarunori original drawing.
Kairiky showing off its skills⁉
It looks so fun!

カイリキー、ピカチュウ、サルノリ の原画をご紹介
カイリキーの“腕の見せどころ”⁉
とっても楽しそうです