We have already seen some leaks from Deadpool 3 that showed some of the film's environments. We're not talking about any major leaks, but including a fight scene between Wolverine and Deadpool. However, the film's director, Shawn Levy, doesn't regret the decision to shoot the films on location, even though they resulted in these leaks. Rather, this was a requirement because he absolutely did not want to overuse greenscreens.
"It bums me out that photos have leaked online. But this is the price we pay for committing to real locations. I made a decision very early in prep that even though Deadpool is now in the MCU, I didn't want another Marvel movie shot on a green screen stage with digital set extensions."
Thanks, Geek Tyrant.