Were she to offer herself as a vessel it would be so simple.
‘Be to do’ used in an ‘if’ clause for suggesting a possible aim when you are saying what must happen in order to achieve it.
Sometimes conditional forms are inverted as a means of sounding more formal. In this case, the conditional 'if’ is dropped and the inverted forms take the place of the if clause.
Use were if the state of being you are describing is in no way the current reality. This is true whenever a hypothetical situation is expressed.
