If you need to add custom Gutenberg buttons, the Button Group block by Getwid allows you to do just that. With its help, you can add one button or a group of buttons along with any content in Gutenberg. Buttons come in several modern styles letting you create rich visual experiences.
Sine Getwid doesn’t override styles of your active WordPress theme, most likely it will output buttons pretty much in style with your overall design! That means you don’t need to work-around it too much. You might be interested in more examples of how it works in the default WordPress Twenty Nineteen theme.