Here are links to them:
Link to Quartet - https://www.linsoul.com/products/kiwi-ears-quartet
Link to Hexa - https://www.amazon.com/Fanmusic-Truthear-Hybird-Earphones-Earbuds/dp/B0BLYT63S3
Link to Zero: Red - https://www.amazon.com/dp/B0C5QWMGM6
Get the Truthear Zero Red variant.
Link - https://www.amazon.com/Fanmusic-TRUTHEAR-Crinacle-Zero-Headphone/dp/B0C5QWMGM6
Get the Red Variant of the Truthear Zero.
Link - https://www.amazon.com/Fanmusic-TRUTHEAR-Crinacle-Zero-Headphone/dp/B0C5QWMGM6
For cables look up Tripowin, Xinhs and Kinera cables
Truthear Zero Red variant.
Link to purchase - https://www.amazon.com/Fanmusic-TRUTHEAR-Crinacle-Zero-Headphone/dp/B0C5QWMGM6
Truthear but not Hexa... It's not very versatile for the wide spectrum of genres from bassy stuff to acoustic and lean vocal stuff... That would be their sibling the Zero:Red.
Link - https://www.amazon.com/Fanmusic-TRUTHEAR-Crinacle-Zero-Headphone/dp/B0C5QWMGM6
Then get her the Project Red.
Yes, get the Truthear Zero Red variant.
Link - https://www.amazon.com/Fanmusic-TRUTHEAR-Crinacle-Zero-Headphone/dp/B0C5QWMGM6
Zero, Red Variant.
Link - https://www.amazon.com/Fanmusic-TRUTHEAR-Crinacle-Zero-Headphone/dp/B0C5QWMGM6
Get the Red Variant. More versatile, also very circuitry changes as the voice could and everything was revamped so yes maybe same internals but revisited and made even better. Tuning much more agreeable with most genres and easy on the ears so less prone to audio fatiguing.
Distortion is nigh unheard of at this price point with how the new Red Variant measures in that department. Get that one.
Link - https://www.amazon.com/Fanmusic-TRUTHEAR-Crinacle-Zero-Headphone/dp/B0C5QWMGM6
Get the Red Variant of the Zero.
Link to purchase - https://www.amazon.com/Fanmusic-TRUTHEAR-Crinacle-Zero-Headphone/dp/B0C5QWMGM6
Get the Truthear Zero: Red