Hi everyone,
I'm looking for recommendations for a gift for my step-daughter. She is 14, so nothing too mature please!
I'd like something with a fantasy twist but that's not essential. What is essential is that the female characters are not sexualized or really "weak" or passive. And that it's not about romance

Read The Casual Chronicles of a Great Saint yesterday. Casual slice of life about cute sleepy saintess doing stuff with her overpowered holy magic.

~4400 manga completed
~1700 ongoing...

I think since this is a gift, OP might be looking for manga actually licensed in English? So I've limited my recommendations to that. Also, note, some of these series are lengthy, so they might not be good one-off gifts.

Completed:
Aria of the Beech Forest (fantasy, slice of life, English publication still ongoing)
A Witch’s Life in a Micro Room (fantasy, slice of life, English publication still ongoing)
Alpi the Soul Sender (fantasy, adventure, English publication still ongoing)
Delicious in Dungeon (fantasy, adventure)
From Far Away (fantasy, romance, adventure)
Generation Witch (fantasy, slice of life)
Helck (fantasy, action, adventure)
Mythical Beast Investigator (fantasy, adventure)
Nicola Traveling Around the Demon's World (fantasy, adventure)
Seven Little Sons of the Dragon (fantasy, anthology)
Shoulder-a-Coffin Kuro (fantasy, adventure)
The Tale of the Outcasts (fantasy, action)

Ongoing:
Flying Witch (fantasy, slice of life)
Hakumei & Mikochi: Tiny Little Life in the Woods (fantasy, slice of life)
The Skull Dragon's Precious Daughter (fantasy, slice of life, adventure)
Sleepy Princess in the Demon Castle (fantasy, comedy, slice of life)
Snow White with the Red Hair (fantasy, adventure)
Witch Hat Atelier (fantasy, drama, adventure)
Yona of the Dawn (fantasy, romance, adventure)

This might be a bit late but I would really recommend Tongari Boushi no Atelier

It's a fantasy manga about a world where you draw magic in patterns on paper with special ink to craft different spells. The main character is a young girl who gets dragged into the witch society and learns about magic and makes friendships. The art and world building is also just fantastic. One of the downsides with this would be that it's not fully released but there are 12 volumes right now released in English!

Physical stuff is only counted by volumes read
Top 10: https://beepingseath.github.io/MangaTop10

If you still haven't found anything, I recommend you buy Bless (SONOYAMA Yukino) (you can try it out before buying lol.)

Maybe it's a bit too adult for a 14 years old, but in the next few years she will probably be able to appreciate it to it's full potential.

It's about learning how to grow up with a fondness and passion for make-up and modeling, in the context of becoming an adult that will either choose to go pro with it or not, and how to keep enjoying such passion.
The two main character either put make-up on models or model themselves, all in all it's about beautiful people and the art of creating fashion icons.

You can find the first three volumes in original english on amazon, published from kodansha comics.

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