There is a speculation that iZu is likely to sign with T1.
According to Japanese community, people thought he signed with Crazy Raccoon being spotted with their members ingame and staying in Japan.
He was going to participate in all star event Rage Valorant in but 4 days ago he posted that he could not go due to urgent issues and went back to Korea.
Today, iZu was spotted playing custom mode in Xdll's scrim without any related japanese pros. Apparently, T1 also had scrims today.
T1 had many chances to play in scrims against JDT during this season, so they might have considered iZu as the best option since then.
They do have saya and Ban as duelists but saya and most of the T1 members need to go to military in the next 2 years so they need to get upcoming talent for roster change and role swaps.
Recently T1 was confirmed to play against KC in 9/16 in Europe, and this seems to be the reason why he can't get to japanese event held in 17th.
Although this is just a speculation as of now, hopefully we'll get the news soon and see him play on the event next month.