Ushiro-kesa-gatame (後袈裟固), the reverse scarf hold.

Osaekomi-waza (hold-downs).
Required for: 3rd Dan (black belt, British Judo Association); 4th Dan (black belt, British Judo Association); 5th Dan (black belt, British Judo Association).

About
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The scarf hold facing the other way: tori sits at uke's right shoulder facing their feet, uke's arm trapped, weight through the chest. A natural landing after some turnovers and armlock entries.

Step by step (standard right-handed form)
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1. Your partner lies on their back; sit beside their right shoulder facing towards their feet, your right hip against their shoulder.
2. Trap their right arm under your right armpit and pin it against your side, gripping cloth at their sleeve or shoulder.
3. Lay your left forearm across their body or grip their belt, and lower your chest onto their chest from this reversed angle.
4. Spread your legs wide along the mat, one forward and one back, soles ready to post.
5. Hold with heaviness through the chest; when they bridge towards you, sink your hip, and when they turn away, follow around with your legs.

Key points
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1. Face their feet, hip tight against their shoulder
2. Trap their right arm under your right armpit
3. Legs wide and braced; ride their bridge with your hips

Receiving it
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The weight arrives facing the wrong way: their hip is at your shoulder and their legs are up past your head, which makes the usual bridge-and-turn feel unfamiliar. Work your trapped arm and turn towards the gap under their chest; keep your breathing low, and tap clearly if you are held and need to stop.

Reference pages elsewhere
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Ushiro-kesa-gatame on the IJF technique reference (International Judo Federation): https://judo.ijf.org/techniques/Ushiro-kesa-gatame

From Waza Book: https://wazabook.com/techniques/ushiro-kesa-gatame/