DLMenu works with this crumbs.json:

{
  "hideMain": "0",
  "showCurrent": "1",

  "tpl": "@CODE:<li itemprop=\"itemListElement\" itemscope itemtype=\"http://schema.org/ListItem\"><meta itemprop=\"position\" content=\"[+iteration+]\" /><a href=\"[+url+]\" title=\"[+e.title+]\" itemprop=\"item\"><span itemprop=\"name\">[+title+]</span></a></li>",

  "tplCurrent": "@CODE:<li class=\"active\" itemprop=\"itemListElement\" itemscope itemtype=\"http://schema.org/ListItem\"><meta itemprop=\"position\" content=\"[+iteration+]\" /><span typeof=\"WebPage\" resource=\"[+url+]\"><span itemprop=\"name\">[+title+]</span></span></li>",

  "ownerTPL": "@CODE:<nav class=\"crumb\"><ol class=\"breadcrumb\" itemscope itemtype=\"http://schema.org/BreadcrumbList\">[+crumbs.wrap+]</ol></nav>",

  "sysKey": "crumbs",
  "urlScheme": "full"
}

nearly as I want.

What I am missing is a possibility to define a different template for the homepage link. This should be:

<li itemprop=\"itemListElement\" itemscope itemtype=\"http://schema.org/ListItem\"><meta itemprop=\"position\" content=\"[+iteration+]\" /><a itemprop=\"item\" href=\"[+url+]\" title=\"Homepage\"><svg class=\"icon icon-home\"><use xlink:href=\"assets/images/icons/symbol-defs.svg#icon-home\"></use></svg><meta itemprop=\"name\" content=\"domain.test\" /></a></li>

In wayfinder snippet it worked well with that config:

<?php
	$hideSubMenus = 1;

/*	if ($modx->config['site_start'] == $modx->documentObject['id']) {
		$homeLink = '';
	} else {*/
		$homeLink = "<li itemprop=\"itemListElement\" itemscope itemtype=\"http://schema.org/ListItem\"><a itemprop=\"item\" href=\"{$modx->config['site_url']}\" title=\"homepage\"><svg class=\"icon icon-home\"><use xlink:href=\"assets/images/icons/symbol-defs.svg#icon-home\"></use></svg><meta itemprop=\"name\" content=\"domain.test\" /></a><meta itemprop=\"position\" content=\"1\" /></li>";
/*	}*/

	$outerTpl = "@CODE:
	<nav class=\"crumb\">
		<ol itemscope itemtype=\"http://schema.org/BreadcrumbList\" class=\"breadcrumb\">
			{$homeLink}[+wf.wrapper+]
		</ol>
	</nav>";

	$innerTpl = "@CODE:[+wf.wrapper+]";

	$rowTpl = "@CODE: ";

	$activeParentRowTpl = "@CODE:<li itemprop=\"itemListElement\" itemscope itemtype=\"http://schema.org/ListItem\"><a itemprop=\"item\" href=\"[+wf.link+]\" title=\"[+wf.title+]\"><span itemprop=\"name\">[+wf.linktext+]</span></a><meta itemprop=\"position\" content=\"[[If? &is=`[+level+]+1` &math=`on`]]\" /></li> [+wf.wrapper+]";

	$hereTpl = "@CODE:<li itemprop=\"itemListElement\" itemscope itemtype=\"http://schema.org/ListItem\"><meta itemprop=\"item\" content=\"[(site_url)][+wf.link+]\" />[[If? &is=`[*id*]:is:1` &then=`` &else=`<span itemprop=\"name\">[+wf.linktext+]</span>`]]<meta itemprop=\"position\" content=\"[[If? &is=`[+level+]+1` &math=`on`]]\" /></li>";
?>

I tried it with If snippet and phx constructs but got in hours no working solution. Has anybody a working example or a hint in the right direction?