Asphalt Legends UNITE supports the following controller formats for single-player features: 

Nintendo Switch™ console with Joy-Con™ controllers attached
dual-controller grip
solo horizontal grip
Nintendo Switch Pro Controller

For Split-Screen mode, the game supports:
dual-controller grip
solo horizontal grip
Nintendo Switch Pro Controller
Please note that Split-Screen mode does not support the Nintendo Switch™ console with Joy-Con™ controllers attached.