[welcome]
Unfortunately, it is up the fish themselves and you will find examples of positive and negative outcomes. In my experience, 2 pairs getting along is far too frequently a temporary situation going bad when an anemone moves, one pair starts breeding, etc.
In my opinion, the risk out weighs any benefit, unless you have multiple tanks immediately available to remove a pair.
fwiw: my 300gal has been too small for many different pairs I have moved through it over the years.