Okada Izo, one of the assassins from the Bakumatsu period, will be in the game. What’s interesting is who plays Okada in Yakuza: Restoration. Kazuhiro Nakatani will voice Okada Izo he also plays Akira Nishikiyama in the Yakuza series. You may recall Akira grew up in the Sunflower Orphanage with Kazuma and was one of the main antagonists in the first Yakuza game.
Yakuza: Restoration also has Saigo Takamori, an influential samurai during the Meiji Restoration. Masami Iwasaki who also plays Ryuji Goda in the Yakuza series will voice Saigo.