For example, let’s say I wanted to start a community around some topic, but I felt that lemmy.dbzer0.com was better suited for it than slrpnk.net. But I want to keep my account on slrpnk.net as the account that moderates the community. Is that possible?
If you can get someone else with a local account to open the community they can hand it over to your slrpnk.net account afterwards. Most of the many previous bugs around moderation functions have been fixed in 0.19.8/9.
However there are two main issues remaining:
You will rarely get any reports as those do not properly federate right now. A fix is supposedly in the works for the next Lemmy release, but this has been promised a few times with limited success.
If de-federated instances differ then you can end up with impossible to moderate situations. For example hexbear.net is blocked by slrpnk.net but it is not blocked by lemmy.dbzer0.com. This means people from that instance can post to the community, but these post are entirely invisible to you as a moderator with an account from slrpnk.net.
My recommendation is that you do not do remote moderation alone. At best you can help someone with an account on that remote instance to moderate a remote community.