You can use asset_get_ids
to get an array of all sprites and call sprite_set_live on each, but note that this can be costly on large projects as the server will have to watch a lot of files for changes.
Typically you might use get_string
and asset_get_index
to make yourself a little debug thing where you can paste a name of a sprite to watch, or make it so that you can press a key to watch the sprite(s) of an instance under the mouse.