as the question is asking for the file types can be forwarded to WildFire for analysis as a part of the "basic WildFire service"
https://docs.paloaltonetworks.com/wildfire/9-0/wildfire-admin/wildfire-overview/wildfire- subscription.html the above page says: "The basic WildFire service is included as part of the Palo Alto Networks next generation firewall and does not require a WildFire subscription. With the basic WildFire service, the firewall can forward portable executable (PE) files for WildFire analysis"
https://docs.paloaltonetworks.com/wildfire/9-0/wildfire-admin/wildfire-overview/wildfire- concepts/file-analysis.html the above page says what are the PE file types: "Portable Executable (PE) files. PEs include executable files, object code, DLLs, FON (fonts), and LNK files, A subscription is not required to forward PE files for WildFire analysis"
"With the basic WildFire service, the firewall can forward portable executable (PE) files for WildFire analysis", look online for PE files and you will get:
.acm, .ax, .cpl, .dll, .drv, .efi, .exe, .mui, .ocx, .scr, .sys, .tsp