I don’t know much about ACT but I think DBT would work well with taking notes or asking to use worksheets. I did CBT for about a year for trauma and found it helpful. That T would have loved it if I had asked to take notes or use worksheets. Current T is more psychodynamic with me. If I needed to take notes he would not have a problem with it other than concern it might distract me from the experience. With him I think I would be more likely to have a notebook in my car and sit in my car after session and take notes.
My long term memory is good but my working memory is aweful so T and I have had to make some adjustments for that.