TOPIC:

Hi. I own a shd studio and use output 1&2 for a main DAC (topping D90) and second output 3&4 for on sub (topping E30) both on SPDIF mode.

Wonder if i can use AES output for 1&2 to D90, which have an AES input and SPDIF 3&4 for E30.
How i must manage software?
Can i mix two kinds of outputs?

As far as I know both outputs carry the same signals. And I don‘t think that you can switch off one of them separately. So you do not need to turn one of them on and  can use them simply in parallel at the same time.

As GBR already correctly answered, all outputs are duplicated: 
OUT1&2 from DSP = AES-EBU 1 = SPDIF1  
OUT3&4 from DSP = AES-EBU 2 = SPDIF2

You can mix and match as you wish. 

DevTeam