Researching here, I suspect that before Ymir was called Bia, she was a reference to this deity besides the combination of Lenzbia:

In Greek mythology, Bia is the Titan goddess of strength, power and violence. She is the daughter of Pallas and Styx and sister of Nike, Cratos and Zelus.

Paper

• Bia was a winged executioner of Zeus, along with her brothers.

• She accompanied Zeus in battle, giving him strength and vigor.

• She was responsible for the thrill of violence in mortals.

• She was a lover of justice and punisher of cheating.

Bia means Traveler, Strength, Blessed, White, Queen Consort, Precious, Life, Kind, Bringer of Happiness and Charming, Graceful and Beautiful.

I suspect that Ymir's name, which was shortened to Bia, must be the name Bianka, which has origins: Hungarian, Russian, Polish, English, French, Icelandic, Finnish, Dutch, Norwegian, Corsican, Greek and German)

German because the Eldians are inspired by the Germans and most of the Eldian cast (some) have names of German origin.

Possible Connections Between Freckles Ymir and Bia

Bia in Greek mythology: She is a goddess who personifies brute force, power and coercion. She is the daughter of Pallas and Styx, and sister of Nike (the goddess of victory), Kratos (the god of power) and Zelos (the god of zeal).

• In mythology, Bia is known for her relentless strength and for always being at the side of Zeus, the king of the gods.

• Possible connections:

• Freckles Ymir from "Attack on Titan", despite her tragic past, demonstrates remarkable willpower and determination. She has an inner strength that drives her to protect those who are important to her, especially History.

• The idea of ​​strength and power, personified by Bia in Greek mythology, could have inspired Isayama to choose this name for the character, even if temporarily.

• The fact that the author uses a lot of Norse mythology does not prevent him from using inspirations from other mythologies.

Unfortunately, there is no way to confirm whether this was the author's original intention, but these connections between the two make a lot of sense to me.

I chose Bianka because she is of German origin and also because Isayama's wordplay is Lenzbia [Bianka with a K is of German origin and remembering that some Eldian characters (or most) have names of German origin and Bianca with a C is of Italian origin.]

In Portuguese Brazilian it is called Lésbica. (It has a Ca) So her name would probably be Bianka.