We could support this via the ellipsis. Otherwise setting the respective column roles could be somewhat easily forgotten.
On the other hand behaviour would differ than compared to as_task_*() from mlr3 as such custom conversions would not be supported there.

@be-marc what do you think?

Example:

data("cookfarm_sample", package = "mlr3spatiotempcv")

# data.frame
as_task_regr_st(cookfarm_sample, target = "PHIHOX",
  coords_as_features = FALSE,
  crs = 26911,
  coordinate_names = c("x", "y"),
  column_role_space = "foo",
  column_role_time = "time"
)

```