@christophe14 In this thread here, you’ll find some options for potentially building /e/. I haven’t tried this yet myself, but the process seems fairly straightforward. I would imagine as long as you’re working with a v7.x of android on your original phone that you’d like to flash, then you may be able to make a workable build. The devs are currently working on /e/ v0.2, which will allow for devices with android v8.x (oreo) to be flashed. My theory is that you’d be able to build for anything v7.x or older, but as I said I haven’t tried this yet myself so I can’t claim for certain that it would work.
If you’ve got the right computer specs to run the build, give it a shot and post how it works! I believe you can build using Ubuntu as long as you have at least 250GB of HD space, and 8GB ram. Windows or Mac won’t work, it has to be linux.