I was applying some super glue to stick back my glue sole. However, some of the glue stained the shoe sole, as shown in the picture below. I have tried using turpentine, but to no avail. Is there any other ways to remove the glue stain?
Chemicals might do more damage than help. I would try some fine sandpaper and a good amount of careful and patient elbow grease.
Recommendation: next time please be A LOT more careful. Or take the shoes to a specialist for repair. Some spill might be expected when the job is done by a non-specialist, but here we are looking at some "horror movie".
When I have to clean off glue, sometimes the only way is to lift up a corner of one part with a knife, and very slowly and gently peel the glue away. Then the next scrap, etc.
The reason it needs to be peeled slowly, is so that the glue can stretch into strands, which become thin enough to break away. If you peel too fast, the bit you are holding will tear off, and you won't be able to remove much at a time, leaving ever smaller fragments behind.