Yes it can but as you probably know, a template node puts a card onto the dashboard (meaning if you add a ui template node, you will have an extra card in the layout)
If you already have a template node on your "home" page, then you can simply add the below to that template.
<style>
.footer {
position: fixed;
left: 0;
bottom: 0;
width: 100%;
background-color: red;
color: white;
text-align: center;
}
</style>
<script>
$("#nr-dashboard-footer").append('<div class="footer"><p>My Footer</p></div>');
</script>
Alternatively, if you have to add a ui-template node (because you dont have one on your home page) then you could hide the card ...
<style>
.footer {
position: fixed;
left: 0;
bottom: 0;
width: 100%;
background-color: red;
color: white;
text-align: center;
}
</style>
<script>
//append a custom footer into #nr-dashboard-footer
$("#nr-dashboard-footer").append('<div class="footer"><p>My Footer</p></div>');
//hide this card. NOTE: a960b1e5.8aec is the Node id as seen in the INFO panel on the sidebar
$('[node-id="a960b1e5.8aec"]').hide();
</script>
NOTE: both of these work but I would consider them hacks.
As there is an element named nr-dashboard-footer
(check your browsers devtools) I suspect there might be a better solution.