In the example below offset should work without animate_offset=True:
import flet as ft
def main(page: ft.Page):
page.add(
ft.Stack(
[
ft.Container(
bgcolor="red",
width=100,
height=100,
left=100,
top=100,
offset=ft.transform.Offset(-0.5, -0.5),
animate_offset=True,
)
],
width=1000,
height=1000,
)
)
ft.app(target=main)