The winner in Sydney is likely to top Group D after both sides won their World Cup openers 1-0.
Wiegman is renowned for not making changes and named the same team for every game at Euro 2022 when the Lionesses were crowned European champions.
She is under pressure to make changes, though, after England scored just once against Haiti, with Chelsea winger Lauren James among those vying to come in.
“I want to make changes,” said Wiegman.
“First of all we see who is fit and available and then we make the decisions to what we need to start with, and then we decide whether we’re going to start with the same XI or maybe make some changes.”
England have scored just one goal from open play since the start of April, but Lucy Bronze is not fazed by criticism over the team’s style.
“You can go the whole way and win the World Cup only winning 1-0 or even drawing games and only winning penalty shootouts,” said the defender.
“Obviously performances mean a lot to us, and the better you perform the more likely you are to win in general.
“But at the end of the day we are winning the games that are important to us. We won the Finalissima. We have won our first game at the World Cup.
“It’s not always about scoring seven or winning 7-3, 7-1 and 4-1.”
England are favourites for the game and will qualify for the last-16 if they win, and China fail to defeat Haiti on Thursday.
Denmark boss Lars Sondergaard has described the Lionesses as a “superpower” of women’s football, and Wiegman said: “We are always the team to beat.”