We released Amphibian, a plugin for IntelliJ IDEA that converts Java code to blocks and vice versa. The initial codebase was branched from the Droplet Editor (used by Pencil Code, Code.org, etc.) that we modified to support various additional languages.
Blanchard, J., Gardner-McCune, C., & Anthony, L. (2019, October). Amphibian: Dual-Modality Representation in Integrated Development Environments. In 2019 IEEE Blocks and Beyond Workshop (B&B) (pp. 83-85). IEEE.
And study being presented at SIGCSE 2020!
Preliminary work on integrating Amphibian into Visual Studio is ongoing.