My two cents are that it might work, depending on what you put into it. Many other people have said the same, and I agree with that. Is there a university that has a speech/language pathology major? They might have good resources. I did an intensive course when I was younger and it worked for a while, but I didn't put in any of the work after it was over, so it didn't stick. My stutter, and I, got worse and worse over time. What I did find is a stuttering support/therapy group that changed my life. I stutter more now, but I hide it a lot less. I'm a lot more confident and I stutter a lot easier. We have been doing our group over zoom, so we have people from all over (including people from Taiwan who join at 5:30 frelling am their time). I have no idea if we will continue to do it over zoom or some kind of hybrid thing, but I hope so. The Irish Stammering Assoc seems to be active, too. They might have resources for you. What ever you do, tho, good luck!