Anker support has completely answered my questions via email here they are:
Q1: What are the max read speeds of SD and Micro SD Card readers? UHS-I? UHS-II? UHs III?
Q2: Does the HDMI port support 4K at 60hz in HDR if the attached computer outputs 4K at 60hz in HDR?
A2: We confirm the HDMI port on the 8-in-1 USB C hub support 4K at 60Hz in HDR if the attached computer outputs 4K at 60Hz in HDR.
Q3.:Is a 100W power supply required to pass BUS power to peripherals attached to the hub? I will only need 30W to charge an M1 MacBook Air. If I used a 60W or 65W charger, will I be able to simultaneously charge my MacBook Air while providing BUS power to two external HDDs via the USB A 3.2 ports?
A3: If you use a 60W or 65W charger, you can simultaneously charge your MacBook Air while supporting two external HDDs via the USB 3.1 Gen 2 ports. The USB 3.1 ports are mainly for data transfer.
Since your MacBook M1 only requires 30W, you can use a 45W or 60W USB C charger with the Anker hub to charge the laptop at full speed because the hub needs 15W for its own operation.