JetPack Related Posts Customizations. https://sridharkatakam.com/jetpack-related-posts-customizations/

gistfile1.php

// change thumbnail size
function jetpackchange_image_size ( $thumbnail_size ) {
	$thumbnail_size['width'] = 350;
	$thumbnail_size['height'] = 200;
//	$thumbnail_size['crop'] = true;
	return $thumbnail_size;
}
add_filter( 'jetpack_relatedposts_filter_thumbnail_size', 'jetpackchange_image_size' );

gistfile2.php

// Remove JP Related Posts from its default location
function jetpackme_remove_rp() {
    $jprp = Jetpack_RelatedPosts::init();
    $callback = array( $jprp, 'filter_add_target_to_dom' );
    remove_filter( 'the_content', $callback, 40 );
}
add_filter( 'wp', 'jetpackme_remove_rp', 20 );

gistfile3.php

add_filter( 'jetpack_relatedposts_post_category_context', 'sk_customize_jp_context', 10, 2 );
function sk_customize_jp_context( $post_cat_context, $category ) {
	$post_cat_context = sprintf(
		// _x( 'In "%s"', 'in {category/tag name}', 'jetpack' ), /* Default */
		_x( '%s', 'in {category/tag name}', 'jetpack' ),
		$category->name
	);

	return $post_cat_context;

}

Using the first snippet of code (gistfile1.php): how can I tell Jetpack to crop the feature images by 300x300px starting from the top left of the image?

I've used this, to no avail:
function jetpackchange_image_size ( $thumbnail_size ) { $thumbnail_size['width'] = 300; $thumbnail_size['height'] = 300; $thumbnail_size['crop'] = array( 'left', 'top'); return $thumbnail_size;