No, using both USB-C ports for the USB-C Snap Hub does not affect HDMI output or charging on the MacBook Neo. The primary connector of the USB-C Snap Hub uses the MacBook Neo USB 3 port for data and video, and the secondary connector uses the MacBook Neo USB 2 port for power. Wi-Fi, Bluetooth, and audio stay fully operational.

• USB-A and USB-C data ports on the hub: up to 5Gbps
• HDMI: up to 4K at 60Hz
• USB-C PD charging: up to 45W