Is Greta Thunberg playing Thanos' daughter in the next Avengers?

The current Avengers Endgame movie had so much potential to play the Thanos / Malthus story further but unfortunately the opportunity is now lost.

If you post story / movie details please add a spoiler warning.

Greta is most likely following her own good intentions but she is just missing a bit education and experience, of course understandsble at her young age.