Are there any Canon or Nikon camera models other than the Canon EOS 5D Mark IV that can upload to ftp automatically after a photo is taken?
We are trying to build a custom workflow. Currently we are doing it with an attached laptop, but it would be nice to have portability.
Magic Lantern has FTP capabilities for Canon EOS 6D.
The website NikonHacker has less developed firmware for Nikon and suggests qDSLRDashboard where an Android, iOS, or Windows application can control some of the camera's features; since source code is available you can make suitable modifications. A cellphone will be more portable than the laptop and can offer extremely fast uploads using LTE.
There's an APP on Play Store called "Camera Upload to FTP", while originally intended to transfer the phone's camera's photos you can change the folder; thus enabling automatic EyeFi transfers to be trampolined. Further searching along those lines is bound to turn up more options.