Hello I'm new with Krita. It looks so nice in hotkeys customisation but I've found no information about making hotkeys for brush presets. It looks handy to use hotkey for that then look for instrument in small window. By saying that I mean press button and it changes a preset from hard pencil to large pencil for example or airbrush. I would like to avoid RMB click menu to change brush preset. In other cases Krita is cool and satisfying

Someone asked this question on Tuesday so my reply to that is fresh in my memory:

You can't directly assign a keyboard shortcut to a brush preset but there is a bult-in script that can manage up to ten different brushes. You'll find this at Tools -> Scripts -> Ten Brushes. This is where you set up the brush presets that can be activated. By default, they are mapped to Ctrl+Alt+(0,1,2, ...9) keyboard shortcuts.

The keyboard shortcuts for each mapped preset can then be changed in the Settings -> Configure Krita - Keyboard Shortcuts in the Scripts - Ten Brushes category by activating Custom instead of Default, if you want to do that.

The 'RMB' on the canvas may be something you want to avoid, for some reason, but it is very flexible once you set it up with your own personal tags.
You may find that the pop-up palette (right-click on the canvas) is more convenient for quickly selecting brushes since it has a nice adjustable graphical presentation and good selection facilities using named tags which you can set up to suit your needs and prefereces in the brush presets docker.