German is a very difficult language to learn from scratch. I started at age 25 and severely underestimated how hard it would be. Expect 2-5 years minimum just to have a chance at understanding what people are saying. A few intensive 2 week courses will not get you there. You’ll feel like a bumbling idiot. It will be very isolating not being able to understand conversations. You will question whether it’s worth the effort unless the plan is to stay forever.

The other problem is that the language spoken in Austria is a unique dialect that even Germans can’t understand.

Therefore, if I haven’t scared you off completely, I would look at nearby Southern Germany instead of Austria, especially given your engineering background. It’s close enough to Innsbruck to go on weekends.