which features I am not going to find in CaptureOne.
As I understand it CaptureOne does not have HDR and Panorama support, what else?
You'll also loose the book, map and slideshow modules for starters.
CO's web page creation is more limited than LR. The DAM features are also less sophisticated. The camera colour calibration profile system is different, using icc profiles, rather than dcp, so you may need new tools for that. Similarly I've not read of a way to create custom lens correction profiles. No visualise spots option to help spot dust marks. no dehaze option. There are less third party plug-ins or presets available too.
The interface and GUI is different, so it may take some effort in learning how to work quickly. I still find LR's GUI more intuitive myself.
It's not all loss though. Besides no subscription and supporting newer cameras than LR6, there are some different ways of working with adjustment layers and tonal corrections that you may find more powerful than LR's local adjustment options.
Overall you can still deliver great files from CO. If HDR and panoramas are important to you, there are stand alone packages that will deliver better results than LR's built in options, it's just a more involved workflow.
Try the trial, work through some tutorials and see if you like it.