How does shorting ETFs work? What are the costs and tax implications?

Question

If I short an ETF stock, how does it work from the cost and tax perspective?

1. Do I get charged ETF expense ratio? (does not make sense to me)

2. If underlying stocks issue dividends, am I charged them? (makes sense)

3. What happens if ETF rebalances its structure - would I be required to counter that rebalancing by buying or selling individual stocks after closing my ETF short? If yes, what would this look like in 1099-B or other tax forms? (seems too complicated to be likely)

I am primarily interested in stock index ETFs but if there are different answers to other types of ETFs (except inverted ones, of course), I'd like to know them as well.

UPD: Corrected that #1 is about ETF expense ratio, commission was not a correct term.

Answer 1

1. No, the expense ratio would be something you wouldn't be charged. If you bought shares of the ETF long, then the dividends are usually reduced by the expense ratio if you wanted to know where to find that charge in general.

2. You would have to make up for any dividends the underlying stocks as part of general shorting since the idea is that once you buy to put back the shares, it has to appear as if they weren't missing in the first place.

3. No, the authorized participant would handle changes to the underlying structure if needed.