You can hook a 5v fan to the headers - I use a 30mm fan and heatsink meant for some raspberry pi models. While there’s no dedicated fan headers, these fans are quiet enough that active speed control isn’t needed - I’ve switched to a metal case but this is the setup I’m using now - and that thread’s probably got some good options for you
You can tap power from the two pins I’ve squared in blue - I guess any pair of red and black headers would work to give you 5v