Sasuke does not have Tsukuyomi. Sasuke uses the Sharingan's standard ability to cast genjutsu through eye contact with its "Eye of Hypnosis". In the past, Sasuke has personally used it on Sai, Orochimaru, and Deidara. We've also seen it used by Itachi, Kakashi, Obito, and Madara on different occasions. What Sasuke has been doing, since Itachi's death, is chanelling these Sharingan Genjutsu through his Mangekyou Sharingan, which apparently has the effect of amplifying its strength, rendering him capable of instantly incapacitating his opponents.
Sasuke is shown casting genjutsu with one eye of his Mangekyou, like how Itachi's casts Tsukuyomi with his left eye [SUP][
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][/SUP] and Amaterasu with his right eye. [SUP][
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][/SUP] But whilst Sasuke typically casts it with his right eye, [SUP][
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][/SUP] he has also done it with his left eye. [SUP][
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][/SUP] Also in his fight against C, Sasuke appears to be holding his left eye. [SUP][
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][/SUP] Additionally, another instance is shown if you count his domination of the Bijuu. [SUP][
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][/SUP]
And even regular Sharingan Genjutsu has been used through a single eye, as demonstrated by Madara [SUP][
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][/SUP] and Itachi. [SUP][
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][/SUP] Itachi himself uses Sharingan Genjutsu with the Mangekyou [SUP][
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][/SUP]after his Tsukuyomi eye had been blinded. Madara has done the same. [SUP][
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][/SUP]
Sasuke has never once called his genjutsu, Tsukuyomi. Both Danzo [SUP][
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][/SUP] and Tobi [SUP][
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][/SUP] compare it to Itachi's Tsukuyomi — understandable considering they're brothers and have both used Amaterasu and Susanoo — but neither of them actually call it Tsukuyomi. Only twice has Sasuke "named" it where he called it "Sharingan" [SUP][
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][/SUP] and "Genjutsu — Sharingan" [SUP][
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][/SUP] respectively, just like Madara. [SUP][
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][/SUP] The time he calls it "Genjutsu — Sharingan" also makes the difference explicit by showing it side-by-side with Itachi's Tsukuyomi.
Tobi implied that Sasuke had received Itachi's eye techniques, [SUP][
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][/SUP] but Itachi had only sealed a single use of the Amaterasu inside Sasuke with the Transcription Seal: Amaterasu, [SUP][
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][/SUP] which Sasuke had no actual control over. From what I've heard, it comes from a misunderstanding over how the Japanese language doesn't differentiate between singular and plural. And when the jutsu was unsealed, his eye transformed into Itachi's Mangekyou Sharingan [SUP][
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][/SUP] temporarily. So if Sasuke used a Tsukuyomi (or another Amaterasu) from Itachi, his eyes would have changed to show it.
The genjutsu Sasuke uses against B resembles the Tsukuyomi with its inverted colours, [SUP][
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][/SUP] but this is also the only time that happens. Every other time we see the genjutsu itself, it doesn't have that visual effect. It's also said by Itachi that the Tsukuyomi can only be broken by an elite Uchiha with the Sharingan (i.e. someone of the Uchiha bloodline with a powerful Sharingan), which was later proven and explained. Yet B was essentially freed with an ordinary assisted Genjutsu dispel.
Ultimately, Sasuke only has Amaterasu, Kagutsuchi, and Susanoo with his Mangekyou Sharingan. Amaterasu was first used with his left eye against Killer B [SUP][
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][/SUP]. Kagutsuchi was used to quell the flames and then used and named when Sasuke went up against the Raikage and where he shaped the black flames, [SUP][
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][/SUP] dubbing it "Enton: Kagutsuchi". The most blatant evidence of these two being his Mangekyou jutsu are when he uses both in the battle against Kaguya. [SUP][
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][/SUP]
Even after Sasuke took Itachi's eyes to awaken the Eternal Mangekyou Sharingan, he has never revealed the Tsukuyomi. You can implant the Mangekyou Sharingan and use the abilities of the original holder (e.g. Kakashi and Madara using Kamui or Danzo using Kotoamatsukami), but when those eyes are used to evolve to the next stage, it instead empowers their own abilities from what we've seen. At the very least, it simply removes the drawbacks.
Once the third databook stated that you would need Amaterasu and Tsukuyomi to awaken the Susanoo, but the above tells us that this is outdated information. If anything, I'd believe that Kishimoto had originally intended to give Sasuke the same jutsu as his brother (with different preferences, perhaps) but decided otherwise at crunch time. As far as we know, the only character with the Tsukuyomi is Uchiha Itachi.
TL;DR: Sasuke's uses Sharingan Genjutsu with his Mangekyou Sharingan and he's only got Amaterasu, Kagutsuchi, and Susanoo as his actual Mangekyou jutsu.
