It is not clear which SbS model you are writing about.
My bad - I should have mentioned it was the ROCKPro64. Pine sells an add-on wireless module in their store for it. I suspect it's a pretty common combo.
ROCKPro64 1x1 Dual Band WIFI 802.11AC/BLUETOOTH 5.0 MODULE - PINE STORE
Note: This module compatible with ROCKPro64 and Quartz64 Model A SBCs. Based on Azurewave AW-CM256SM Combo Module and made specifically for the ROCKPro64 SBC.…
pine64.com
The mainline LibreELEC includes the module and also one for the ASM1166 PCI card I have plugged into the board for sata drives.