If the mouldings are soft wood, and possibly even if they are not,
you're likely to rough it up quite a bit as you get off that last coat.
I used to make sandblasted signs out of redwood, cedar, and sometimes
oak. The blasting would remove wood more easlily, and therefore more
deeply, in the areas between the growth rings, so the result had
grooves from slight to 1/4" deep depending on the particular piece of
wood!
I'd find ANY other way, before I sandblasted my wood trim
BTW, sandblasting IS a legitimate and common practice to remove paint
from stucco in my area.