Thank you bcworkz, finally I understood how add_filter() and get_sidebar() work.
I’ve done like this: load_template ( dirname( __FILE__ ) . '/sidebar-mytype.php' ) ;
Hello!
The problem with sidebar is that different themes use different layot, so there are a lot of errors when calling sidebar from the theme.
Currently I work on separate sidebar for the plugin, it will be in the next version.