The Noctua NF-A9 PWM (92cm 4 pins) seems to fit, but the connector is not the same. The TerraMaster is expecting JST XH (2.5mm) header, which is different than the Noctua header.

The Noctua has this wiring (as per https://noctua.at/pub/media/wysiwyg/Noc ... _paper.pdf): blue, green, yellow, black

I had to remove the Noctua header and replace with a JST and change the wires to the following: black, yellow, green, blue

Not sure why it has to be reverted, but it worked (I tested it).
Maybe this will help someone in the future.
Related thread:
viewtopic.php?t=1272

