Honkai: Star Rail All Stickers in Dreamscape Pass (Version 2.2)

Boothill: After everything has concluded, return to where the absurd dream fell.
Teleport to Penacony Grand Theater at the Weekly Boss and walk forward a little bit. Interact with the floating book.

Jazz: Complete Dream Song and record Dr. Blues' story
Complete Dream Song Adventure Mission by interacting with Dr. Blues in Dreamflux Reef. The quest is easy enough for you to complete without any guide, and you can get one (out of two) achievement of it.

Hanunue: Complete the final Hanu's Adventure and obtain Hanu's Planet of Festivities Collectible Card.
Complete the Hanu's End Adventure Mission at the spot below (Can only start after you complete all the Hanu's readable) and you'll get this sticker.

Famous Five Origamists: Finish all the Origami Birds' stories and obtain the Famous Five Origamist's Planet of Festivities Collectible Card
Complete Dream Song Adventure Mission by interacting with Dr. Blues in Dreamflux Reef. The quest is easy enough for you to complete without any guide, and you can get one (out of two) achievement of it.

Graffiti 1: Unlocked by Default

Graffiti 2: Unlocked by Default

Graffiti 3: Unlocked by Default

Streetside Repose: Explore the vacant alleyways of Dreamflux Reef, and trace the footsteps of the Dreamflux Gang.
Head to the southwest part of Dreamflux Gang and you will meet a group of Vagrant. Complete the hidden task and obtain an achievement + sticker.

Watchmaker's Hat: Obtained by progressing the Trailblaze Mission.

Mikhail's Slumber: Chat with the guardian of Dreamflux Reef. Progress through the Trailblaze Mission to meet Micah. Or you may not be able to interact with him.

The Existence of God: Explore the Dreamflux Reef and residential area and learn about the God of Innumerable Iron Cans.
Go to Slumbertown until you can find the Emanator of Cans. Complete the hidden task to get an achievement + sticker.

Old Friend: Investigate the statue next to the Watchmaker.
Go to the top of Dreamflux Reef (by progressing through Trailblaze Mission) and interact with the dog statue on the right of the Watchmaker.

Slumbertown: Investigate the twisted spiral in Dreamflux Reef.
Near the Origami Birds gathering are a black hole. Go to the edge and there will be an option of Memoria Black Hole.

The Essense of Dreams: Investigate the giant rusty Clockie.
Go to F1 of Dreamflux Reef near the huge Clockie statue and investigate the gate.

Lost Diary: Soldier
Obtained from next to the railing at the Dreamflux Reef residential area.
Interact with the floating book at the edge of Slumbertown.

Lost Diary: Dancer
Obtained from next to the singer at Dreamflux Reef.
Interact with the floating book in front of a cute-looking van near the singer and Origami Birds.

Lost Diary: Vagrant
Obtained from the Dreamflux Reef station.
Go to F1 of Dreamflux Reef and interact with the floating book.

Lost Diary: Affluent Man
Obtained from close to a certain dumpster in Dreamflux Reef.
Go to Jessie's Snack at the northwest of Dreamflux Reef and outside her restaurant has a huge dumpster. Interact with the floating book there.

On Set: Unlocked by Default

Brand Ambassador: Fix Garcia's Emo Dial
You can find Garcia in the Audition Plaza of the SoulGlad Scorchsand. Talk to him 3 times and use the Calm Gear to get the sticker.

Action: Unlocked by Default

Sponsor: Help the Soda Bottle you ran into at the entrance of the venue to complete the audition.
Interact with the Soda Bottle in Location 1 on the chair to start a hidden task. After that, go to Location 2 to find the Soda Bottle once again and get the sticker.

Base Camp: Obtained at the end of the Brother Hanu stage.
Go to the F2 of Gunfire Time: Gunfire Trial to get the floating book at the end of the corridor.

Lonely Giant: Obtained at the end of the giant Dream Ticker stage.
Interact with the floating book near the Boss Stone balloon behind the huge Dream Ticker statue.

Festival's Starting Point: Obtained at the entrance to the audition venue.
Right in front of Aideen in the middle of Audition Plaza.

The Birth of a Superstar: Obtained at the end of the audition venue.
Right beside the Path of Superstar space anchor.

Foxian's Contestant's Note: Unlocked by Default.

Masked Fool's Contestant Note: Complete any Easter Egg stage after the audition ends.
You can get this sticker after completing any of the 6 hidden challenges in the Auditon Plaza. Check this guide for the whole guide: All Hidden Challenges in SoulGlad Scorchsand Audition Venue

Knight of Beauty Contestant's Note: After the audition is over, find a hidden room in the venue.
Go to Floor No. ??? of Gunfire Time: Gunfire Trial to get the floating book in front of the lift.

All-Seeing Eye: Try to use clockwork against a blackbird.
Talk to Lady Black Claw near the 3D room entrance and change her mood to Angry.

Intermission: Obtained at the reception hall of the theater.
As description mentioned, interact with the floating book in the middle of the reception room.

Where Starlight Congregate: Obtained from the stage's entrance.
On the platform above the space anchor in the Grand Theater.

Program List: Complete Robin's assignment.
Once you complete the 2.2 Trailblaze Mission, you will get a message from Robin near the space anchor below in Penacony Grand Theater. Complete the mission to get an achievement and a sticker.

Dancer 1: After everything has concluded, return to the room of chaos in the theater.
In front of the 3D room entrance at the southwest of the theater.

Dancer 2: After everything has concluded, return to the room of harmony in the theater.
Interact with the floating book outside of the VIP room at the southwest of the Grand Theater.

Dancer 3: After everything has concluded, return to the room of order in the theater.
In front of the 3D room entrance at the southeast of the theater.

Tomorrow in Harmonious Chords: Unlocked by Default.

Present Inebriated in Revelry: Unlocked by Default.

Past Confined and Caged: Unlocked by Default.

Dream Rehearsal (I): Comfort the tired Dreamscape Repair Worker.
Talk to Olma in the reception room and change her mood to any other mood before changing it again to Happy.

Dream Rehearsal (II): Listening to the story of George the Dreamweaver.
Talk to George in the reception room and change his mood to Happy.

Dream Rehearsal (III): Learn that the conductor thinks about the Charmony Festival.
Talk to Toskani who is hiding behind the 3D room entrance and change his mood to Sad.