Aggregating two 4G/3G data links from 2 different sims?
As far as i know, the modem only exist one 4G.
You can use it in both SIM (switch it) but you can't use both at the same time.
Even if you're thinking using the first one is 4G and the last one is 3G, it won't work. It's dual-band not dual channel, and beside it will make your phone a lot thirstier than before and i'm pretty sure you don't want that.