This depends on a number of factors. The charts from Chia.net say a K32 plot takes 256 GB of temp space maximum.
But, it starts at 0 GB and the size keeps growing until it reaches it’s max size at the end of phase2. From phase 3 the size starts going down until it reaches the final size of 106GB at the end of phase 4.
So if you use a stagger that spreads the plots out so they are running in different phases from each other, you can fit more plots on the same space. 8 plots is for sure possible, maybe even 9-10.
However:
The write speed (sustained! write speed, so not the advertised speed on the box) of the drive is also important. If a drive has a low write speed, it might struggle to do anything more than 4 plots at the same time.
Have a look at the sustained write speed graph here for reference: