Advise for Itinerary for 7 days in Italy and Austria, starting in Italy, ending in Austria, not interested in Vienna,
Your allotted time is really not long enough to do either country justice. Sorry you're not interested in Vienna, one of the premier old European cities in the continental style..
Remember your first and last day of any trip is wasted, as is every day you travel from city to city.
I'd fly into Venice and stay 2 nights. Then catch the train up to Innsbruck to see The Alps. It's a short train over to Salzburg. Munich has a great airport, and it's maybe a 2 hr. train ride Salzburg-Munich.
One country or the other and, at that, no more than two cities/locations. Rome and Venice, Venice and Florence, Rome and Florence all make a good week. Or just Rome.
Salzburg and Innsbruck perhaps in Austria?
What do you like to do? What are your interests? What time of year?