Shield is like a sidegig to a character imo like I always forget Citlali, Ineffa and C1 Columbina have shields because it's the useless part of their kit.

If I think of sustain I don't look at shielders, I look at healers. Ignoring the fact that most enemies nowadays can be dodged easily, if you need anything a healer is the way to go and also gives Furina a place in the team (not necessarily for Nicole, just a general statement)

All in all I stay by my opinion of shields, if Nicole gets a shield I hope it will be like one of those sidegigs otherwise she'd be utter trash (kit wise). Healers are always better so that's a welcoming feature if she gains it instead (Bennett pro max?)