Short answer
4LAND is the best bet for the areas around Riva del Garda and Trento, but as of January 2023 they still lack coverage for parts of Alto Adige / Südtirol north of Brixen / Bressanone.
Medium-length answer
Good maps: Geo4Map, 4LAND, l'Escursionista, Fraternali (check coverage for your region).
Poor maps: Tabacco
Bad maps: IGC
Terrible maps: Kompass
Long answer
The quality and availability of Italian topographic maps varies greatly per region. The underlying problem is that the Italian topographic service has no proper base map of the country. The last time they mapped the whole country was in Mussolini times. Since the 1950s they seem to be about halfway through in a new survey. So you're left with commercial publishers, but those rely on official base maps; they don't fly around with their own survey planes. At best, they check out local hiking trails and the status of huts and shelters. Therefore, the quality of such commercial maps depends on the quality of the underlying base map. Between commercial publishers, quality (beauty, readability, reliability) varies considerably.
I'm including some publishers here that don't currently cover the area you are interested in, because (1) this may change, and (2) others may read this post and be interested in other areas.
Good hiking maps for Northern Italy:
- Geo4Map, excellent maps. So far mostly cover Piemonte and not much in Lombardia or Trentino-Südtirol-Alto Adige yet, possibly because the region of Piemonte couldn't wait for the Italian state and has made its own pretty good topographic base map. Stay tuned as Geo4Map may start to cover your region soon.
- 4LAND publish good maps. They seem to have some coverage in your area, but check to be sure.
- L'Escursionista. Almost as good as Geo4Map, but same problem, no coverage further east yet.
- Fraternali. Quite good, but again coverage further west than you seek.
Poor maps for Northern Italy:
- Tabacco maps aren't great, but may be the best you can find. If a trail is on Tabacco and also on Openstreetmap, it's probably there. If it's on Tabacco but not on Openstreetmap, chances are it has vanished.
Bad maps for Northern Italy:
- IGC (scale 1:50,000). Their maps are ugly and unreliable. They frequently draw trails or huts in completely the wrong place. Use with utmost care only as a matter of last resort.
- Avoid Kompass under any circumstances. They only serve as kindle and not even for that they're not great. You're better off without any map. Avoid Kompass. Did I mention to avoid Kompass? It is amazing how a publisher that makes reasonable cycling maps in Germany can make such terrible maps in Italy, but they do.
There are many smaller publishers that are hit-or-miss, such as maps from local towns or national parks. In my experience, there is a positive correlation between how good a map looks and how reliable it is, but there are outliers. Near the Swiss border you could use Swiss topographic maps. They look great, but on the Italian side they depend on Italian information which may be last surveyed in Mussolini days. If you like to explore if you can locate a trail that was last regularly used in the 1950s, they're a great source. If you just want to hike, not so much. (Of course, Swiss maps in Switzerland are the best maps in the world, but that is a different question entirely.)
The wildcard:
- Find a WMS or tiling server, load it in QGIS with hiking trails from OSM on top, export it on A1 and have it printed at your local copy shop. I've done that once (not in Italy) and all was good, except that the print shop thought A1 = poster and printed it on way too high quality, heavy, and thick paper that I could barely fold into a map…
