A Personal Offering

The choices given on this quest are full of references to the original 1-10 questing experience in Teldrassil! Since they haven't been listed yet, they are:

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• A sachet of rare earth from Darnassus.
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• A carefully preserved selection of herbs, gifted by Tarindrella long ago.
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• A pressed moonpetal lily from Shadowglen.
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• A smooth stone from the road to Darnassus.
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• A sigil from your first trainer.
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• A skein of webwood spider silk from Shadowglen.
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• Something else that is valuable to me.
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A really nice touch. Some of my night elves still have those very herbs in their bank from years ago, so I chose that offer. Tyrande gives the same response regardless of which option you choose.

For anybody, who wants to do this on a character that hasn't played Dragonflight at all, here is what you need to do. (I had to search like an idiot because there are a million ! in Valdraken when you go there fresh 70).

Also, be sure you are doing this on a Night Elf character, other races can't unlock the transmog.

The Coalition of Flames
Fire Season (starts in Valdraken, easy to miss in the sea of quests you have available)
Dousing the Wards
Eyes of Fire
Through the Flames
Inflammatory Information
Raise the Alarm

There is no quest leading you here but your questlog will just have a hint to go there next:

Emerald Dream Campaign
Call of the Dream
(There is a lot of other quest available here, you can ignore them all, each time you come back here you only need to accept the one quest that's next in the chain.)
Emerald Welcome
Feast or Flaming
Wild Gods in Our Midst
Burning Assault
The Face of Our Enemies
The Cruel
Amirdrassil
Lost to the Flame
Between Fyrakk and a Hard Place
Home in the Dream
A Multi-Front Battle

Druids of the Flame
The Burning Barrow
Not Yet Lost
The Smoldering Copse
Burning Ground
Grim Reprisal
Forlorn Hope
The Looming Cinder

Ice and Fire
Mayhem Incarnate
Light 'Em Up!
Best Laid Plans
Primalist Directive
Finding Terro
Assault on the Wellspring
Big Bright Beautiful Barrier
Power, Eruption, and Lies
Tactical Withdrawal

Eye of Ysera
Eye of Ysera
A New Brute
Fire Watch
In and Out Scout
Disarm Specialist
Good Counsel
Putting Roots Down
Merithra's Gambit
Might of the Forest
Triple Threat
Flight and Fight
The Ember Still Smolders

A Dream of Fields and Fire
The Bloom Begins
Forward Unto Fire
Hazardous Horticulture
A Clash of Ice and Fire
Defense of the Ancients
A Scrap of Hope
Fighting Fire With Fire
The Age of Mortals
Aerial Supremacy
Echo of the Firelands

Amirdrassil, the Dream's Hope: Fyrakk If you did this quest already on another character you can skip this. Talk to Tyrande in front of the raid entrance to start the next quest. Else you need to kill the Boss inside the raid.

New Beginnings
A Blossom Witnessed
A Changed Land
Auspicious Gathering
Offerings for the Well
A Personal Offering You made it! Congratulation!
New Moon
Something Worth Celebrating

All the choices give the same response from Tyrande.

I accept your offering with warmth and gratitude, [Your Name].