If you have a universal time for both worlds, that would be a perfect use case for story arcs.
For two different calendars, there are currently only workarounds, which are suggested and discussed elsewhere in this forum. Here, for example:
If you have a universal time for both worlds, that would be a perfect use case for story arcs.
For two different calendars, there are currently only workarounds, which are suggested and discussed elsewhere in this forum. Here, for example: