I spent about $9 for (2) JD Digital USB Type-C to USB OTG Cables by Revain, paid. When I upgraded my cellphone, the newer phones use a faster USB-C slot. These cables allow me to connect a flash drive to my cellphone and transfer files. The second cable works great as a backup. Both work great. Just make sure you "disable" the connection by selecting the option on your phone before disconnecting the USB stick from the cable. Just follow the pop-up instructions on your phone.
Cable Baseus Cafule USB - Lightning, 1 m, black/red
26 Review
Portable battery with wireless charging support COMMO Magnetic Power Bank, 4 600 mAh, graphite
23 Review
4K / 30Hz USB-C to HDMI Adapter - 3-in-1 Type-C Converter Cable for MacBook Pro, MacBook, Mac Pro, iMac, Chromebook, and USB 3.0 Type-C Devices (2017/2018)
13 Review
Ultimate Compatibility: USB C to HDMI Adapter for MacBook, iPad, Dell, Surface & More
12 Review