February - last edited February
@grandadsmurf If your computer runs 64-bit Windows, you can simply tell Origin to run the 64-bit version of Sims 4. Open your game library, right-click on the Sims 4 icon, select Game Properties > Advanced Launch Options, and choose 64-bit from the dropdown menu. Having the Legacy Edition installed won't change this.
You could try uninstalling the LE, but Origin will likely redownload it unless you stop it in time, so it's usually easier to just leave it in place if you don't absolutely need the 6 GB of drive space.
If Origin keeps telling you to run the Legacy Edition, or switching automatically, the problem may be your antivirus blocking or even deleting TS4_x64.exe. In that case, a game repair (right-click on the Sims 4 icon in your game library, select Repair) should put it back. Then you'll need to set exceptions for Origin.exe and TS4_x64.exe.