Free tool
BIMI is how a brand logo shows next to its mail in supporting inboxes. It takes a TXT record at default._bimi.domain pointing at an SVG logo, usually a verified mark certificate, and above all a DMARC policy set to reject or quarantine. This check reads the record and the DMARC policy. The logo and certificate are not downloaded.
What this checks
Four things, in order: DMARC at p=quarantine or p=reject with pct=100 (and ideally sp= too), consistent SPF/DKIM alignment so DMARC actually passes, an SVG Tiny P/S logo on HTTPS, and for Gmail and Apple Mail a VMC (needs a registered trademark) or a CMC (needs the logo in use for a year). The DNS record itself is the easy part: v=BIMI1; l=logo URL; a=certificate URL at default._bimi.domain. Providers also look at sending reputation, so a new domain may not get the logo even with everything in place.
Related tools
Mailboxes in Luxembourg
NovaNode Mail gives you the MX, SPF, DKIM and DMARC records to copy into your DNS, with mailboxes stored in Luxembourg.