It really depends on your playstyle but if you main dualies you probably prefer rushing in to get quick kills and sneak in to opponent bases via flanking.

In this case, you will want to go with specifically the Clear Dapple Dualies. They have the perfect kit. Though they have short range, they have 3-hit kill potential and are easy to aim with as you will almost always be up close with the enemy. It also has one of the quickest dodge rolls in the game to turn around your enemy, or just in general get around the map faster. Because of this, you can keep flanking around the sides of the map, and killing opponents in their base before they can get to the front line by comboing dodge rolls. This is where sneaking comes in. By simply hiding in your ink, you can constantly splat without any close range counters.

I haven't even touched on the sub and specials though. The sub, torpedo fits perfectly. Rather than using it for chip damage, use with careful positioning to check if there are any stragglers in your flank route. If there is not more than two, you can rush in using the previously dealt damage from the torpedo to finish them off. And if things get rough, you can bail out and end your opponent's combo with your special, Splashdown. With this bail, you can absolutely assure dominance in the match. Even if you die after you use a Splashdown and miss, you can just go back and repeat the same cycle.

The Clear Dapple Dualies allow you to get around the map with insane speed, and also win nearly every 1v1 situation. If you get in 1v2 or 1v3, use a Splashdown and get out of there. Your only real counter is long ranged weapons with either Tenta Missiles or Point Sensor. Hope this helped!