Using an SD card on the moto g7 play

Your phone supports an optional microSD card up to 512 GB.

The type to buy depends on how you'll format the card:

Portable storage (can use card in different devices): A Class 2, 4, or 6 card is sufficient.
 
Internal storage (card used only by phone): Use a high speed card such as UHS-1 type for best performance. Class 2, 4, or 6 cards are slower than your phone’s internal storage, so using them for internal storage would slow your phone's performance.