The "Legacy Edition" is a specific version of FIFA released for the Switch that focuses on updated visual assets rather than new gameplay features.
Any site claiming to offer a "free download" for a retail Switch game is likely distributing pirated software or malware. What is the "Legacy Edition"? FIFA 20 Legacy Edition Switch Free Download
The gameplay mechanics and modes are identical to FIFA 19. The "Legacy Edition" is a specific version of
Key additions from the PS4/Xbox versions, like the VOLTA street football mode, are entirely absent from the Switch version. Legitimate Ways to Play Now like the VOLTA street football mode