USB C to DisplayPort hub works with VGA but not HDMI
Yes, you'll need an active DisplayPort to HDMI adapter for this to work. A passive adapter does not work.

The reason this doesn't seem intuitive is that many DisplayPorts ports are of the "DisplayPort++" type (also called dual-mode). Those are able to automatically detect when used with HDMI, and then the port outputs a signal specifically for HDMI. The non-++ DisplayPort ports on your hub does not do that - and thus need an active adapter for converting the signal.

You can use an adapter such as this:

https://www.amazon.com/dp/B00EDT0072

It sounds like you've left out some part of the explanation on how you got it working with a HP laptop - as the same limitation should apply there.

Note: If you intend to connect two displays for extended desktop, this hub won't work. Connecting two seperate displays requires support of MST, which macOS does not offer. You'll need to use a Thunderbolt 3 adapter or dock instead.