QRServ takes any selected files on your device and makes them available through its own HTTP server at an unused port number. The selected files can then be downloaded via web browser on another device and/or software that allows file downloads over HTTP from QR codes.
Devices involved would need to be on the same network (i.e. access point, tethering [no mobile data required], VPN [with a supported configuration]).

Features:
- QR Code
- Import via sharesheet
- Multi-file selection support
- In-app and via sharesheet
- Selection is put into a ZIP archive
- Tooltip when press and holding on the resulting archive file name will reveal the originally selected files
- Direct access mode
- Large files? Use direct access mode to use direct access to internal storage as to avoid attempting to copy the selection into app cache
- The file manager for this mode only supports single file selection
- The mode can be toggled by pressing on the SD card icon
- Share option
- Show and hide filename in download URL path
- Long press the share button to toggle
- Various IP addresses from different network interfaces can be chosen
- HTTP server uses an unused ("random") port
- Supports various languages: English, French, German, Hungarian, Italian, Polish, Portuguese, Spanish, Russian, Turkish

Permission usage:
- android.permission.INTERNET -- Collection of available network interfaces and port binding for the HTTP server
- android.permission.READ_EXTERNAL_STORAGE -- Read-only access to emulated, physical SD card(s) and USB mass storage
- android.permission.MANAGE_EXTERNAL_STORAGE -- Direct access to select files on internal storage rather than what gets cached first

QRServ is open source and available for desktop.
https://github.com/uintdev/qrserv