Interesting. IIRC, Sony was one of those that were most awkward to make region-free (if not impossible).
I have two now-ageing LiteOn recorders and a fairly recent LG, and these were dead easy to change (just a few numbers on the remote control). I also have an elderly £20 Alba player (Homebase once sold them), and despite it saying 'Region 2' one the box, not only plays American Region
1 NTSC discs (as well as Region 2 PAL), but also has the option of outputting either the original NTCS composite video (3.57MHz colour), or the more usual pseudo-PAL (525-line, 4.43MHz).