I am working on a commentary on the Psalms. I have decided to compile some helpful links that I discovered during my research. It includes a mix of exegetical and sermonic links. Here is what I have for Psalm 91 (in no particular order). Feel free to mention any that you find helpful in the comments section.
Analysis by C. J. Labuschagne: https://www.labuschagne.nl/ps091.pdf
William Barrick’s notes: https://drbarrick.org/files/studynotes/Psalms/Ps_091.pdf
The Fathers on Psalm 91: https://pursuingveritas.com/2019/10/22/the-fathers-on-psalm-91
God Shelters the Faithful: The Prayer of Psalm 91 by Matthias Henze: https://www.thetorah.com/article/god-shelters-the-faithful-the-prayer-of-psalm-91
Danny Akin (outline, manuscript, audio): https://www.danielakin.com/living-under-the-shadow-of-the-almighty-through-the-psalms-series
Psalm 91 devotional: https://www.generations.org/devotionals/104