Reverse-Flip page layout

in your child theme, create a folder /template-parts/ (if it does not exist already);

add a file named reverse-layout-page.php into that folder;

copy the code of page.php of the parent theme into that file;

edit the top section in that file to:

/**
 Template Name: Reverse Layout
 * 
 * forces two column page layout - reversed - regardless of theme options 'Page Layout' setting
 */

in functions.php of the child theme, add:

add_filter( 'body_class', 'reverse_layout_page_body_classes', 12 );

function reverse_layout_page_body_classes( $classes ) {
    if ( is_page_template( 'template-parts/reverse-layout-page.php' ) ) {
        if( in_array('page-one-column', $classes) ) {
			unset( $classes[array_search('page-one-column', $classes)] );
			$classes[] = 'page-two-column';
		}
    	$classes[] = 'reverse-layout';
	}
	return $classes;
}

in style.css of the child theme, add:

@media screen and (min-width: 48em) {
	
	body.reverse-layout:not(.has-sidebar):not(.page-one-column) .page-header,
	body.reverse-layout.page-two-column:not(.archive) #primary .entry-header, 
	body.reverse-layout.page-two-column.archive:not(.has-sidebar) #primary .page-header
	{
	  float: right;
	}
	
	body.reverse-layout.page-two-column:not(.archive) #primary .entry-content,
	body.reverse-layout.page-two-column #comments
	{
	  float: left;
	}	
}

not widely tested, if you find minor layout issues, please come back here.