If it is a canon-brand APSC lens, it's EF-S (and, of course, you're using an adapter), the camera will automatically switch to crop mode.
Other brands, the camera may not switch automatically (my R5 doesn't switch for my Tamron lenses). But if you change it yourself, you should get good results.
Thanks for the feed back. I have a canon 18-135 I will try it. But most of my others lens are sigma. I have a 18-300 i need to try. I have a Tokina 12-24 for APSC. will try it too.
Yes, they work in the sense that you get images. Just be aware that you’re getting a 7.8MP image. I was all set to enjoy my 18-135 and 55-250 with my EOS R until I actually shot with the combo—I was so underwhelmed by the output that I sold both of them immediately.
well I have a Sigma 18-300 that I can use on my 7D2 and I have a olde 12-24 tokina Lucky I have all otehr lens are FF 24-105 and sigma 150-600 and 100-400. I was thinking to get the RF-24-240