Eighth-ranked Wales got their campaign off to a win with a penalty goal landed by replacement halfback Keira Bevan to beat Scotland 18-15.
Cunningham has left the Wales backline unchanged but has been forced to make four changes in the pack. That came about after flanker Alisha Butchers was ruled out of the rest of the tournament after suffering a bad knee injury.
Lock Gwen Crabb has moved to the blindside flank, Siwan Lillicrap will captain the side when starting at lock, while Bethan Lewis will start on the openside flank. Kelsey Jones will start at hooker after Carys Phillips suffered an ankle injury.
Cunningham said: "We're playing New Zealand in their home World Cup, we're both on the back of wins, so it's all about this game now.
"We have nothing to lose, but you have to be brave against any New Zealand team. You have to go for it and score tries. We can't hold back. We have to go for it.
"Australia showed you can create opportunities, and we need to do that too."
Cunningham wants a similar start they made against Scotland.
"We started well against Scotland, scored two tries, but created more scoring opportunities. We probably left two tries out there.
"If we can take more of those opportunities, we'll be in a much better place come Sunday evening."