I found out you can use your PS4 controllers with your Switch.
Orzly Pro USB Dongle Wireless Controller Converter for Nintendo Switch - Includes Type C Adapter for Gamepad Mode Use - (Supports Most Xbox, Playstation, and 3rd Party BluTooth Wireless Controllers)
https://www.amazon.ca/dp/B07CQSP983/..._oCDaCb1BTDTPX
Works great both wired and wireless without delay.
Now I got enough controllers for 4 player Smash.