After installation, return to the Switch home menu. Hover over FIFA 19. Press + on the controller. Go to "Software Update" -> "Version". It should read "Ver. 1.0.4" .
If you are looking to update your FIFA 19 NSP file to the latest version (v1.13) to access current squads, fix bugs, or play online (via Local Wireless/LAN mode), here is a comprehensive guide on how to do it safely and correctly. fifa 19 switch nsp update full
If you are looking for the original gameplay features updated via the final official software version: After installation, return to the Switch home menu
If you want to extract/analyze the update yourself: fifa 19 switch nsp update full