Hi Henrique,
Thank you for sharing this with us! Both methods work with polygons, whether using bake as Alembic or Point Cash Tag, and the Tag might have some advantages, such as not needing reference files. However, in Brian’s case, where he wants to apply this to a Spline, the Tag doesn’t seem to work, so we have no choice but to use bake as Alembic, as in the screen recording below.