Clash
 
Clash's original outfit (A) Was produced Clash Blond ponytail disguise
First appears in Starbright Part 1: Falling Star and again in:

Starbright Part 2: Colliding Stars, Starbright Part 3: Rising Star, The Rock Fashion Book.

After this point it is replaced by "The New Clash", and finally by Clash (C).
Makes it's first and only appearance in Starbright Part 3: Rising Star. 
Clash Snowmobile outfit Clash Workout Gear
First appears in Last Resorts and again in:

Video Wars (reused footage). 
Makes it's first and only appearance in Last Resorts.
Clash Ski Race outfit Clash Reporter Disguise
Makes it's first and only appearance in Last Resorts. 
Makes it's first and only appearance in The Jem Jam Part 1.
Clash Permed Hair Disguise The New Clash
Makes it's first and only appearance in The Jem Jam Part 1.
This is a modification of the first original outfit (A) that debuted in Starbright Part 1: Falling Star.

First and only appearance is in Glitter and Gold.

Note that "The New Clash" (shown only in Glitter and Gold) has longer hair with only a slight suggestion of a rat-tail, also for whatever reason, her makeup is mirrored.  Her belt looks more like the doll's belt and the shoes are also pink. After this point it is replaced by Clash's original outfit C), which is basically the original version, but with all purple hair instead of red & blue.

The Jem Model sheet information for this fashion is simply "The New Clash."
Clash Cleaning Lady Disguise
Clash Purple Triangle Dress (Jem Disguise #1)
Makes it's first and only appearance in One Jem Too Many.

*I guessed on the footwear.  They actually kinda match!
Makes it's first and only appearance (on Clash, anyway) in One Jem Too Many.

*Jem also wears this fashion.
Clash white corset Striped Dress (Jem Disguise #2) Clash's Original outfit (C)
Makes it's first and only appearance (on Clash, anyway) in One Jem Too Many.

*Jem also wears this fashion.
First appears in Father's Day and again in:

Video Wars.

Note that this fashion is Clash's original outfit, except with all-purple hair in place of the red and blue streaked hair.
Clash Pink Tuxedo Suit Clash Rose/black white dress
First appears in Father's Day and again in:

Aztec Enchantment, Video Wars.

Thanks to Cosmic Falcon for donating this drawing to the wardrobe section!
First appears in Father's Day and again in:

Video Wars. (Clash in Video disguise)
Clash Pink/Black/White party dress Clask Black Fringes Vest
First appears in Father's Day and again in:

Video Wars.
First appears in Aztec Enchantment and again in:
Clash/Sarah Clash Bathing Suit
Makes it's first and only appearance in Video Wars.
Makes it's first and only appearance in Change of Heart.