So i read that every stamina dps build use a bow as secondary weapon, now i want to play 2H/2H or maybe 2H/DW is that viable for open world and normal/vet dungeons?
Just to give a bit more insight, bow back bar is recommended mostly for Volley, and Poison Arrow as well as being able to DPS the boss during phases where melee can't reach them. It's just the best of options.
If you want to forfeit the bow I'd recommend grabbing Caltrops as the AoE fracture can prove useful in PvE content for trash pulls and clears; it's not useful for damage currently and you won't need to cast it during most boss fights so it could be swapped out in between. Usually for trash the taunt doesn't apple fracture on everything.
A reasonable switch out for Volley is the Undaunted skill Trapping Webs morphed into Shadow Silk. On paper it will deal as much as volley and gives a synergy for your group to use which will mostly be the healer.
Another suitable skill to sub in so that you have some ranged DoTs is Soul Trap.
Hopefully someone else can come and give some more suggestions; I haven't used 2H/2H or DW myself as a build yet.
Yeah every Stamina DPS build does that. Out of my 9 Stam DPS chars I have 2 using a bow, the NB and the Necro, see every single one.
To the 2H/DW, I feel like Bow and Dual wield are completely exchangeable, it really doesn't matter which one you use, you get the same results with either of them.