In the past, I've housed a male OHM betta (Gabe) with female guppies no problem. He was the most gentlemanly betta I've known. Never bothered the females. I used to call them his 'harem" as kind of a ironic joke.
Honestly, it all depends on what personality your fish has. Obviously, certain tail types contribute to certain personality traits, but that is not always the case. I think that crowntails tend to be more aggressive than say, halfmoons or OHMs, but each fish has their own level of aggression.
A good way, and good method I've learned, is to introduce a betta to a new tank mate AFTER the new tank mate has been in the tank for a few days. That obviously means taking the betta out so that the new tank mates can settle in and establish territories. This will make the betta think he is not in his territory and won't act as aggressive.
This may or may not work with your betta, so be very observant of the tank after the introduction to see if any flaring, chasing, fin nipping etc. on the betta's part happens. If there is any of these actions, remove the betta from the tank. These behavioral signs mean that the betta is obviously not meant to be in a community tank.
“The day the power of love overrules the love of power, the world will know peace.”
― Mahatma Gandhi