Hi all,
happy to see that discussion and interest.
I am not very familiar with ZCash features how to proof the transfer from/to z addresses. For Monero there is the tx key and with that it is possible to verify the transfer, which is required in case of a dispute so that the mediator can check if the transfer was made or not. The auto-confirm feature we just added a few months ago is only for that XMR feature, so the release of the BTC from the XMR receiver is done automatically and the user do not need to click manually “payment received”. This speeds up trades. Such a feature would not be required initially, in fact its probably not even wanted as it would require trusted Bisq contributors to run such infrastructure nodes and that comes with costs and need to be justified by the trade volume (which is in XMR justified but most other altcoins have much lower trade volume).
As many OS projects we are short on dev resources, so if any dev from here want to work on that it would go faster for sure. Otherwise best is to make a very clear description what is needed as a Bisq proposal at Issues · bisq-network/proposals · GitHub and then hopefully some dev pick it up and implements it. In the best case if there is a tool to verify the z tx, it could be implemented quite easily.
But some complications might arise from how it should be supported to mix z and t txs? Some users might not care so mixing it would work, but others (most?) would care, so we would have basically 2 diff. coins, but that partitions the market… so all those considerations should be in the proposal…