I'm a bit confused about columbina's lore

Yes

I just take it as your normal time travel shenanigans where there two of her at one point in time

I guess she was born and lived till the present then went through the moon gate. Travelled back in time, met her sisters then turned her body into kuuvaki and left her soul behind. Sandrone's equation summons Columbina's soul from the moons reflections and the kuuvaki reforms around her soul to recreate her body. The exact circumstances around her birth is probably a future plot point with all the other timey-wimey stuff.

Its a time loop. All the energy in nod krai belongs to her, since she spread it out in the past. Her sisters said “this (kuuvhaki) is your power…” meaning past Columbina was always there.

Just think about how like in tears of the kingdom dragon zelda and zelda existed at the same time.

It’s a bit of a bootstrap paradox. She essentially created herself and led herself to everyone and set up her own return. But to do that she had to know to do it in the first place so who told her to do it the very first time? Then when she returns she branches off and continues life but she does a bit of a loop.

As dr who put it, if you go back in time with Beathovens sheet notes and want them signed but beathoven doesn’t exist so you publish the notes as beathoven instead to keep the “image” of beathoven alive. Then you get the same notes you get in the future and take back to get signed…where’d the notes come from? Catch 22.

Her birth 500 years ago was "natural", her rebirth in the AQ is what she influenced.

When she's with the moon sisters and sends her body to Teyvat in the form of Kuuvaki, it happens at a time where the moon sisters are alive, so before she was born 500 years ago.

Basically, 500 years ago her "cycle" begins, then in the present she enters the moon gate, her soul goes back thousands of years into the past (with a fragment remaining in the present in the form of lunnotar), and in that distant past she sets the ingredients that lead to the final moments of her "present" life and her possible rebirth. Then she "dies" in the past and is reborn in the present.

If you were to represent time as sheet of paper and *her* time as a line going in one direction on that sheet, her birth 500 years ago is her starting point, and when the events of the AQ happen, that line makes a turn and goes backwards, beyond the starting point, then when it reaches the part with the moon sisters, it makes another turn again and goes back to the present (further than before the first turn, and it keeps going from here). But it never crosses with/connects back to the starting point.