Hey broow
You can use the Management interface if you have Internet Access on that. If you don't have internet access at all, you have to do it manually.
Download the Files from your switch:
Device# license smart save usage all bootflash:all_rum.txt
Device# copy bootflash:all_rum.txt tftp://10.8.0.6/all_rum.txt
Upload in Smart License Portal. This is for version 17.3. Be careful, they changed smart licenses between 16.6 and 17.3
https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst9300/software/release/17-3/configuration_guide/sys_mgmt/b_173_sys_mgmt_9300_cg/sl_using_policy.html#Cisco_Concept.dita_7057e18c-3c69-4d91-841b-0b5beb7a2d88
That's the guide for 9300, but I guess it is no different for 9500.
Regards