England are the top scorers in Qatar with 11 goals and eight different scorers following Sunday’s 3-0 win over Senegal in the last-16.
Southgate has stuck with a back four and a variation of 4-3-3 in the first four games but, historically, the manager has tended to switch to a back five against top-level opponents, like the win over Germany in the last-16 of Euro 2020 and the defeat to Italy in the Final.
To reach consecutive World Cup semi-finals, England will surely have to stop Mbappe, who has already scored five times at the finals, and moving Kyle Walker to the right of a back three would help counter the forward’s explosive pace.
But asked if he was tempted to be safer against Les Bleus, Southgate said: "We’ve always got to get the balance of the team right.
"We’re wanting to be positive, we feel we’ve done that so far in this tournament. I think we’ve got energy in the team, we’ve got legs in the team, we’ve got depth in the squad. So I don’t think we should be drifting too far from what we’ve been.
"You’ve obviously got to make allowances for the opposition and find out where you can exploit them but we’ve got good players to come in as well."
Southgate added: "There is a lot of experience [in the squad] of these moments and they know that they’ve had to win games in different ways, they’ve had to come from behind in big matches.
"What we talked about against Senegal was keeping the relentless pressure going, not sitting back when we were ahead, making sure that we kept the intensity of our game. So we’ve got to do that now against the world champions."
Switching to a back five would likely mean sacrificing a midfielder and Southgate will be wary of changing a system which allowed Jude Bellingham to thrive against the African champions.
Bellingham was given licence with to roam as Jordan Henderson and Declan Rice anchored the midfield, and the teenager set up the opening goal for the Liverpool captain before starting the move for England’s second, scored by Harry Kane.
"I felt the game against the States, we were putting tremendous responsibility on Jude and that was a game which was difficult to work out the midfield, the pressing and the problem solving and we thought Jordan helped that and we think he is giving Jude a bit more freedom to go," Southgate said.
"He does not need to be quite as positionally disciplined. At the moment, he is still young and is still learning when to press and when not to press.
"The positive of that is he turns over so many balls and regains them for you. But it means we’ve got a bit of balance and I think this is the best version of Hendo we’ve had. He looks in good physical condition, touch wood. His influence on the group is fantastic, always has been. And to chip in with a goal, he really deserves that."
Meanwhile, Southgate says he will remind the squad that extra security is available after Raheem Sterling returned to the UK to be with his family following a break-in at the Chelsea forward’s home.
England training - Behind the scenes
"We had offered [extra security] to players," Southgate said. "Without talking about the individual details too much because I think it’s important we respect his privacy.
"That was something we did discuss with the players before we left. I think there’s a little bit [for Raheem] in the midst of moving house that played a part in that. But we are very conscious of it. And with what’s happened, we will have that conversation again."