You'd have to check the motherboard spec, most fan headers only support up to 1A, so you wouldn't want to plug in fans that exceed the output of each fan header. Generally why most adapters etc. when it comes to power draw are often advised against as generally it means it doesn't support that configuration.
But the motherboard spec would have to be referenced, which I can't seem to find anywhere !
According to specs, you have 2 headers.
Cpu_fan is pwm, so with splitters/hub that are powered by the psu not the motherboard, you can have upto 10 fans because that's the limit of the pwm signal, after that it's too week to make the fans work. Any fans connected here will operate according to cpu temps.
Sys_fan is DC voltage. Here the 1A rule really applies, 0.9A max is safer. Since most normal fans run @ 0.3-0.5A each, you can use only 2 maybe 3. Fans on this header will operate according to motherboard/case temps. There are no normal powered hubs/splitters for DC voltage fans as it's the voltage itself which changes and voltage from the psu doesn't. You'd need either a fan controller that goes in a 5.25" optical bay or a high end hub such as the Commander Pro which is software controlled, so can change voltages for the fans.
So technically you can operate upto 13 fans in total, but 10 will have to be cpu and upto 3 others, but you cannot mix them, the 10 must be 4pin PWM and the 3 must be DC 3pin.
If you want any control. If you just want fans to spin at max, use molex adapters straight to the psu and add as many as you want.