I don't think the new sketch layer is supported in 3.x widgets because this layer is a bit different from Map Notes and the symbols used are vector based which are also not supported in 3.x.
How are you using this sketch layer?
Hi. Thanks for helping me out with this. We have developed a simple road debris pickup request tracking solution that uses an agol-hosted web app to record requests in the office and a field maps map to locate and complete requests. Occasionally, additional information about the location is available, but the info has no value after the request is completed so it does not need to be incorporated into the existing data model. I was hoping to use the sketch layer (map notes) to provide this extra information to field staff. Hope that makes sense. Thanks.