MacBook Pro Internet Recovery

Internet/Network Recovery of El Capitan or Later on a Clean Disk

If possible back up your files before proceeding.

1. Restart the computer. Immediately after the chime hold down the (Command-Option-Shift-R) keys until a globe appears.
2. The Utility Menu will appear in from 5-20 minutes. Be patient.
3. Select Disk Utility and click on the Continue button.
4. When Disk Utility loads select the drive (usually, the out-dented entry) from the side list.
5. Click on the Erase tab in Disk Utility's main window. A panel will drop down.
6. Set the partition scheme to GUID.
7. Set the Format type to APFS (SSDs only) or Mac OS Extended (Journaled.)
8. Click on the Apply button, then click on the Done button when it activates.
9. Quit Disk Utility and return to the Utility Menu.
10. Select Reinstall OS X and click on the Continue button.

Note:

1. To install the version of OS X that was currently installed use Command-Option-R.

2. To install the original factory version when the computer was new use Command-Option-Shift-R.

if you have made a working bootable USB-stick Installer, you do not use Internet Recovery to employ it -- you boot from it, either by setting it as the default startup drive and restarting, or by holding the Alt/Option key at Startup, and waiting for up to five minutes for the USB stick to be "discovered".

They both booted the Mac to Internet recovery mode.

I have made over a dozen different USB-stick Installers for many different systems including the two you mentioned. They have NEVER booted to Recovery-anything.

As far as I can tell, a properly-made Installer stick boots to a stand-alone Installer, and does not use the Internet except very, very late in the process for one last validation.

Then your USB-stick Installer is not bootable, or not made correctly, or damaged.

How to create a bootable installer for macOS - Apple Support

.