Trick Room: Trick Room only makes it so that the slower Pokemon attacks first, it doesn't change the Pokemon's speed but rather the turn order. So Gyro Ball's Power will be exactly the same if Trick Room is used.

Sheer Force: Raising the user's stat would be considered a positive secondary effect so with Flame Charge its Power will rise to 65 but it'll lose the secondary effect of increasing the user's speed.

At least that is how it's suppose to work, according to Bulbapedia there are a few things it does which it shouldn't be doing (such as giving the Attack boost you get from a Life Orb but deactivating the Life Orb's secondary effect of decreasing HP when a move that'll have Sheer Force activate (such as Flame Charge). It also for some reason deactivated the Escape Button, Shell Bell, and Red Card Hold Item). So there looks to be some hiccups with it, however from what I read it should work as the way I said it should above.

Well let's take a closer look at the two:

Pokemon: Zoroark

Type: Dark
Ability: Illusion (Will take the appearance, species name, Pokeball, gender, and shininess (if any) of the last Pokemon on your team. If hit it'll "break" the Illusion)
Stats:
* HP: 60
* Attack: 105
* Defense: 60
* Special Attack: 120
* Special Defense: 60
* Speed: 105
* Total: 510
Weaknesses (2x): Fighting & Bug
Resistances (.5x): Ghost & Dark
Immunities (0x): Psychic
Moves Analysis:
It can learn Fire-type moves Flamethrower (TM35) and Incinerate (TM59) to deal with Bug-types, if you had Bred it with a male Vulpix, Ninetales, Nuzleaf, or Shiftry that knows Psychic-type moves Extrasensory it'll get it as an Egg Move which should handle any Fighting-types, or you can teach it Flying-type Aerial Ace (TM40) and deal with both types which would probably be the recommended strategy. After that nothing too fantastic, by leveling it mostly learns Dark-type moves with some Normal-type and Psychic-type status moves mixed in (it learns Normal-type Scratch and Fury Swipes and also the Bug-type U-Turn, but the rest of its attacking moves are Dark-types, and even then the only strong Dark-type attacks it has are Foul Play (level 29), Nigh Slash (Level 30), and Night Burst (level 64)). From there it learns the usual TM moves almost every Pokemon can learn and nothing impressive from Egg Moves (though it does have strong Dark-type moves like Dark Pulse and Sucker Punch).
Strategy:
With Zoroark, the strategy here is with its Ability Illusion. You want to fool people into attacking you with a move with Zoroark is either resistant or immune too so in the last member of your team you should have a Pokemon weak to its resistant/immunity (so that's a Ghost- or Psychic-type for both its resistances (Ghost or Dark-type) and a Fighting- or Poison-type for its immunity of Psychic-types. Personally I would pick a Ghost-type as no one would attack a Ghost-type with a Fighting-type move (being Ghost-types are immune to Fighting-types) and Ghost-types other weakness is Dark- and Ghost-type which you resist). You can try buying more time by using Double Team (TM32) or, if you want to risk Zoroark's already low HP, Substitute (TM90). While most of the time the Illusion will only be a neat trick, when you go up against its weakness you have a chance to do a sneak attack before your opponent realizes that you're using a Zoroark. Heck, for maximum fun have a Sableye or Spiritomb last in your party and really mess with your opponent.

Pokemon: Bisharp

Type: Dark/Steel
Ability:
* Competitiveness (Raises Attack stat by 2 stages if opponent lowers any of your stats (including Attack)
* Inner Focus (Prevents flinching)
* Pressure (Dream World Ability)
- (In Battle: Doubles the PP usage by a foe or any moves an ally Pokemon uses which does damage to the Pokemon with this Ability)
- (Outside Battle: If first in your party, it increases your chance of encountering a high-leveled Wild Pokemon by 50%)
Stats:
* HP: 65
* Attack: 125
* Defense: 100
* Special Attack: 60
* Special Defense: 70
* Speed: 70
* Total: 490
Weaknesses (4x): Fighting
Weaknesses (2x): Ground & Fire
Resistances (.5x): Normal, Flying, Rock, Steel, Grass, Ice, & Dragon
Resistances (.25x): Ghost & Dark
Immunities (0x): Psychic & Poison
Moves Analysis:
It can learn Flying-type Aerial Ace (TM40) for Fighting-types, Grass-type Grass Knot (TM86) for Ground-type, Ground-type Dig (TM28 ) for Fire-types, Rock-type Rock Tomb (TM39) & Stone Edge (TM71) for Fire-types, and if you Bred one with a male Kadabra or Alakazam and it knew Psychic-type Psycho Cut it'll know it to deal with Fighting-types further (though if you were to choose one, I'd go with Aerial Ace as you HAVE TO take care of the Fighting-type weakness, not like it could take that much hits from its other weaknesses...). Nothing much after that, it learns by leveling up mostly Dark- and Steel-type moves with a few Normal- and Bug-type moves thrown in. As always it knows the usual TM moves and Breeding has nothing interesting. Though note that being its a Steel-type it won't get hurt by Sandstorms which it can learn via TM37.
Strategy:
You want the Ability Competitiveness and focus just mostly on Physical attacking moves, it'll rip things to shred if you do.

MY CHOICE: Zoroark

REASON: The problem with both of these Pokemon is that they can't take a lot of hits and even with Bisharp's 100 in Defense its HP is still too low to last for long. Thus you're going to need Speed and a strong stat with that Pokemon specializes in which Zoroark has. In addition you might be able to buy more time with its Illusion Ability, long enough to do a counter-attack.

Only (Physical) Defense; Special Defense will still be vulnerable to stat reduction.

...............yes........

Yes, Zorua evolves into Zoroark, however the only way to get a Zorua is either by the Celebi Event or breeding the female Zoroark from the Legendary Beast Event, so most often then not you'll probably first have to breed a Zoroark to get a Zorua egg before training a Zorua.