As reportage illustrations are mostly made on location, artists tend to use materials and processes which are safe as well as accessible allowing them to freely portray the intended sense of their chosen place. Artists who work remotely on online live events or other digital briefs tend to use an ipad/wacom tablet as their canvas and softwares such as adobe, procreate, tagtool, zenbrush, inspire pro, etc to create visuals which are accessible for themselves and their clients.
Depending on the illustrator, it can vary how they’d like to be approached; Katie Chappell’s process of working with clients is something along the lines of: “somebody gets in touch/fills in the event details, we then discuss more over call/email, do loads of tech rehearsals to make sure everything works and looks how the client wishes it to look and finally the event takes place where I illustrate the conversation live — the clients pretty much receive the drawings/videos right after the event.” Illustrators such as Jenny Soep who work with live performances of experimental music/art scenes often let the sounds around them direct their choice of medium and use the music to improvise the atmosphere in their illustrations.

Sources:

Katie Chappell Illustrator. (n.d.). About Katie Chappell. [online] Available at: https://www.katiechappell.com/about-katie-chappell

Embury, G. and Minichiello, M. (2018). Reportage illustration : visual journalism. London; New York, Ny: Bloomsbury Visual Arts, An Imprint Of Bloomsbury Publishing Plc.

Taria (n.d.). What is Reportage Illustration? [online] Available at: https://urbansketchingworld.com/what-is-reportage-illustration/?utm_content=cmp-true