>>532753575
If you enter red S3 via manual de-activate she's 100% auto retreat once it's over. Regular S3 she can use her talent and regen back fine if she took lethal dmg
The red S3 duration is only 10s so it's identical to silence-alt immortal duration. Hoshis is 10s of potential immortal time while silence is 60s of potential time but 10s when it actually kills an ally.

So realistically she's not any better than silence-alt for abusing scenarios like izumik. Hoshi herself is just a more useful op in general, but the immortality abuse is the same. They just slapped it on a better op