Does the job!

I’ve just installed this plugin to replace another one that only sorted subsites alphabetically, but since it hasn’t been updated in a few months I went ahead and found this one.

It gives you a very simple interface to visually reorder your multisite listing using drag and drop rows.

Works well enough for me, but I have less than 30 subsites. I wouldn’t know how it works for a large amount of subsites, could be kind of difficult to reorder such a long list. I’ve already added it to my two multisite installs, and it is going to my list of multisite must-have tools.

Using it on WP 6.0.0 and apparently works well.