In Power BI Desktop I am running into an issue where I cannot format visualizations that are part of a group. When selecting the visualization in the group and navigating to the Format visual tab, no options are available and it says "Formatting options are unavailable for this visual". The only workaround is to ungroup the visualization, make formating changes, then re-group it with the other visualizations. This has been happening for the past week or two. Sometimes it will let me format visualizations in a group, but most of the time it shows the message below.
I tried again and still can't reproduce the problem, also haven't found ICM reported internally. If the problem persists, I suggest you create a support ticket, it's free for pro user and a dedicated engineer will come to dig the problem for you.