I'm not sure that I believe this. It's a CR "zero" for me.
A few years ago it would have made very good sense to have 2 versions of the 5 series, i.e. one high res and one for sports, but it seems less relevant now. If indeed we did get hi-res and sports versions, I assume we'd be looking at 90MP and 20fps for the hi-res version, and 45MP and 40fps for the sports version (although that would *seriously* undermine sales of R3). But the R5 can *already* shoot 45MP at 20fps, and I'd already taken it as granted that after 3-4 years Canon would be *capable* of producing a successor with 60MP and 30fps, at a price not much higher than the upcoming Z8.
An alternative pairing, which to me would make more sense, would be to have one stills-oriented version and one video-oriented version. Both would be hybrids, but the emphasis on each would differ markedly. The stills version might be 60MP, 20fps, a *tllting* or Panasonic-style tilt/flippy screen and minimal video-features, while the video version would basically be a R5C Mkii.
But my overall verdict is to take this rumour with a bucketful rather than a pinch of salt. I think we'll just get one model - probably 45MP, 30fps, flippy screen, better AF, some AI "features" and just possibly a new more powerful battery.