Responses
Wasn't the setting that the Saintess will be Liz rival, isn't the duke daughter a bit too old for the crown prince? I don't really remember the beginning of the series, but all future events should be around Liz.
that was supposed to be the plan, blonde with blue eyes probably an illegitimate daughter, however it seems since FL and ML riled up the harrismans, the current harrisman daughter became the one who got used in the experiment and thus became the saintess, advancing the plans ahead 10 years of the supposed timeline
Maybe the fake Saintess was the blond daughter of the duke that's why the high priest reaction was like that and why she went to imperial palace just a theory