Throwbacks

[Enkidoh]

The OP wants FFXI's original AF designs which are completely different to FFXIV's - alas I don't see that happening. As Mikko mentioned there are other FFXI oufits in the game (there's also the Wootz armour which is the Koenig armour).

But it should be mentioned that pretty much every past FF game has had fanservice/reference gear in FFXIV now:


FFI: the Labyrinth of the Ancients tank set (Armour of Light) is based on Yoshitaka Amano's artwork of the Warrior of Light from FFI. Additionally his blade and shield from this design are seperately attainable from Seat of Sacrifice EX. His helmet from this design is gained seperately through the Collector's Edition of ARR.
FFII: The Wild Rose set based on Yoshitaka Amano's artwork of Firion from FFII is a Veteran Reward.
FFIII: The two Onion armour sets along with the Onion Helms reference the Onion Knight Job from FFIII. (The original Onion Doublet set is from FFXIV 1.0 and in ARR is attainable through Retainer Quick Ventures. The original Onion Helm was a limited offer gained through a code included with the Collector's Edition of FFXIV 1.0, with a Red Onion Helm also attainable through Retainer Quick Ventures. 1.0 also had a third black Onion Helm (the Peregine Helm), but this doesn't seem to have returned in ARR and is unattainable. The Onion Armour set is also the Labyrinth of the Ancients LNC/DRG set, with an Onion Shield for GLA/PLD gained from Mor Dhona via tomestones of Poetics). A number of other Labyrinth of the Ancients and Crystal Tower armour sets also reference characters and enemies from FFIII.
FFIV: The Moonward gear gained through tomestone vendors in Endwalker are based on Yoshitaka Amano's designs of FFIV's cast (such as the tank set is based on Amano's artwork of Cecil's PLD form). The Baron Helm and Baron Circlet offered through HW's Collector's Edition and preordering HW respectively are also based on Cecil's headgear (for his DRK and PLD forms respectively).
FFV: the Wayfarer's attire gained in the EW 6.1 patch story is clearly based on Bartz's outfit from FFV. The Chicken Knife for RDM gained through preordering SB also was from FFV.
FFVI: the Gambler's cloak available from Gold Saucer is directly based on Yoshitaka Amano's artwork of Setzer from FFVI. Additionally the GSM AF set is clearly meant to reference Amano's design of Locke from FFVI.
FFVII: Cloud's outfit from FFVII Advent Children is available as a veteran reward. Incidentally his Buster Sword appears not as a weapon but as the level 2 melee DPS Limit Break.
FFVIII: Squall's outfit from Kingdom Hearts II and Dissidia Final Fantasy appears as the final veteran reward. Additionally his Revolver gunblade for GNB is available as part of the Collector's Edition for ShB, the name of his ultimate weapon Lionheart shows up as the level 80 AF weapon for GNB (but differs in design), and the name of Seifer's unique gunblade Hyperion likewise is the name of the level 89/90 AF weapon for GNB in EW.
FFIX: Zidane's oufit from FFIX appears as a veteran reward.
FFX: Tidus and Yuna's oufits are available for purchase on the Mogstation.
FFXI: Iroha's oufit from FFXI Rhapsodies of Vana'diel was a special event reward. Additionally a number of FFXI gear pieces have returned as previously mentioned (Vermillion Cloak, Fire Staff, Scorpion Harness, Optical Hat, Kirin's Osode, all from Eureka - also Koenig's armour is available as Wootz armour which is a crafted set for tanks and a seperate set with the same model for DRG/RPR). Also the level 89/90 AF weapon for GLA/PLD is named Lightbringer, and the level 89/90 AF weapon for DRK is named Chaosbringer, both weapons from FFXI (Lightbringer was a story element of the San d'Orian main scenario story in FFXI that was unattainable by players, and Chaosbringer was a great sword that DRK characters in FFXI could gain after a special quest). Finally, the Death Scythe is a bonus item included with the Collector's Edition of EW which is a glamour weapon for RPR, this was a great scythe equippable by DRKs in FFXI.
FFXII: the Law's armour sets from Bozja content are based on Judge gear from FFXII. Also some is based on FFXII's characters (such as Vaan, Penelo and Balthier).
FFXIII: Lightning and Snow's oufits were formerly available as rewards through a special event, but are now available for purchase from the Mogstation.
FFXV: Noctis's outfit was formerly rewarded through a special event in game, but is currently unattainable.
Tactics: like the FFXII sets, class and NPC gear from FFT is found through the Return to Ivalice raids, fittingly.

If I'm missing anything or made a mistake, please let me know!