I partially solved my problem. So I answer my own question :D
I was messing with traffic shaper wizard, I found out that, if I create same queue name on both WAN and LAN, lets say qP2P, and if I set a floating rule for P2P traffic and set its queue name qP2P ( without ackqueue, its important). Download traffic goes to LAN's qP2P and upload traffic goes to WAN's qP2P, ack packets also goes to these queues. So I solved my own problem.
But I couldn't solve my latency problem entirely,
If I fully saturate upload (WAN traffic) my latencies dont get affected that much. I have read that WAN traffic is the one that we can control, the traffic that we can actually control by prioritizing packets or dropping, it is the the traffic that we create. On the other hand, download traffic is the one that we cannot control directly, someone could send us packets and we cannot stop it until it reaches our pfsense router.
So my problem starts here, when i fully saturate my download traffic, latencies start to go high, not high as 600ms or 900ms but 200-250 ms.
I'm testing latencies with ping command, i gave it highest priority, i tested different schedulers, for both LAN and WAN, I couldn't solve this problem.
Traffic shaper solves my bandwith problem, I can enjoy smooth web browsing, every queue can get its fair share of bandwith, but latencies are too high for gaming when download queues are saturated
So experienced users can give me an advice, is it normal to have high latencies like mine, can it be solved?
Thank you in advance