I'd say she's a good namesake. She advises
Antigone not to bury Polynices, as the punishment for doing so is death, and makes it clear she finds her sister's course of action foolish, but when
Antigone is caught,
Ismene declares she has aided her (despite not having done so) and that she too deserves death.
Antigone, however, exposes her lie so as not to allow her sister to become a martyr, and thus,
Ismene becomes the most tragic of her siblings by virtue of having outlived them all.
masculine list:
https://www.behindthename.com/pnl/191050/124079feminine list:
https://www.behindthename.com/pnl/191050/124080