Normally, you’d just turn east after crossing the border, cutting ca 200km and a ferry ticket from the trip (which would be ca 3h), but this is apple’s suggestion. Don’t get me started on the longer eastern option, which would be quite costly. (I don’t have anything configured to avoid.)
Do a detour, go via Sønderborg and Gråsten straight to Sønderhav, enjoy the best ristet hotdog at Annies Kiosk, do the rest of the tour - Profit