The Oznat bring two profiles to bear one with short range weapons the other medium, and both bring smoke. The First, with combi rifle, smoke LGL, and a Shock CCW is best used in a link where extra burst and BS can mitigate the otherwise standard BS.
The second profile, with a boarding shotgun, smoke grenades, and DA ccw, is better at close range, has a higher chance to land smoke by using PH instead of BS, and can destroy objectives if necessary in CC (though it is far from adept at doing so.
Though she possesses no special melee skills, her CC of 21 and melee bonuses from a Hungries link could allow her to get work done in melee. This risky maneuver is probably best left to the Hungries though.
With PH 13 and Kinematica 1, the Oznat has some ability to dodge, but is often better off using smoke to avoid fire fights. ARM 1 and BTS 0 mean she is not going to take a hit well, so keep her out of harm's way when possible.
All smoke special tricks apply to the oznat as well: she can lay it down to let models move up table, to buff MSV 2 troopers, to get into melee, or allow a model with a direct template weapon to Intuitive Attack while imposing a -6 on its targets.
If using the oznat un-linked, be sure to put her at least 6" away from any enemy ARO since it is expensive to remove her impetuous order.
Linked Oznats in the Morat Aggression Forces are by far the most common way you will see an Oznat. In that function she will serve as link leader for the Hungries Gakis and Pretas. Killing her WILL NOT break the link unless she is the link leader, however she add a lot of effectiveness to the link and should be targeted when possible.
Outside of a link, lining up AROs against the Oznat can be an efficient way to take her out.
Most other shooters will do well against her.
If you are looking for smoke, look to a Daturazi Witch-Soldiers who can do this better and cheaper. The Oznat Boarding shotgun can be a nice pressure piece in very low point games given her high speed. Generally, the reason to bring her is the Hungries Control Device to allow them to be brought in Morat Aggression Forces.
The Oznat is more valuable than a Daturazi Witch-Soldiers even though you will often want to play her she same way. Deploy her at least 6" from any possible ARO.
Active Turn Role
The Oznat when not in a link will look to deploy smoke where it is needed, or possibly move into a good place to make use of her shotgun.
In a link team she will run along with the Hungries and accompany them up table. The Hungries fireteam as a whole has one of two options. Either it will stay back in the Morat DZ and provide five orders to as low as 34 points (an under-rated tactic), or they will look to move up field using their climbing, movement, and Dogged on the Pretas to cause as much damage as they can to the enemy. This can leave the Oznat stranded, but at the low cost of her link it isn't too hard to get your investment back.
With PH higher that BS the Oznat often wants to dodge and use her Kinematica to get to safety. If she is in a good position to make use of her smoke grenades, this will be a better defensive option. At extremely close ranges though, don't discount the bonuses provided by the boarding shotgun.
Last of all, remember that Engage dodges enemy attacks AND puts you in close combat, where she is happy to be.