I can confirm this bug as I tried Yosei as my general for the tournament and he wasn't accepted.
Other generals that weren't accepted, possibly because of the legendary type missing:
-
Ezuri, Renegade Leader (I even tried putting another copy of him to play in debug mode and it worked).
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Karn, Silver Golem (I'm not sure if it's because of missing legendary status, but I don't think EDH mode checks color identity issues so
Karn should have nothing else disallowing him)
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Experiment Kraj (I don't know what's the cause, but he wasn't allowed as a commander and my deck seemed otherwise legal).