I think all of them. But I am not sure. I was interested in ETFs only.
Depending on the fund, issuing commission is ~0.8-1% but it can significantly dropped e.g. to 0.3%. Custody fees unfortunately are a % of the investment amount with no upper limit. They start from 0.35% and they are harder to drop.
Correct + as I mentioned, some do not mind the extra admin fees for “peace of mind” or for broker diversification or for UBS employees.
Well ETF is also a fund 
The Duo Savings offer includes all UBS ETFs for sure.