In order to celebrate a fantastic year of Community Days,
every Pokémon species featured during these events will appear in the wild again, all around the world,
for a special weekend-long event, from Friday, November 30, at 1 p.m. PST to Sunday,
December 2, at 11 p.m. PST.
All of the featured moves from each Community Day will also be available,
so your evolved Pokémon can get them!
Additionally, special bonuses will be available for just three hours in each region.
See more details below:

原文を読んでみると、技マシンでレガシー技ゲットできるとは一言も書いていない。


1. 今までにコミュニティデイで出てきたポケモンが出現すること
2. 進化させたポケモンがレガシー技を覚えること

この二点だけが確定で「evolved Pokémon」の意味を「当日以前に進化させたポケモン」と勝手に解釈するなら技マシンの可能性はあるけど、ちゃんと文章の流れを見るとそこまで書いてない