Definitely do not put all your eggs in the online shopping basket. There are too many out there who are fakes, flakes, pic hunters, catfishing, etc. As suggested: get out to some clubs or parties and meet real people. We have never connected with a single lady or unicorn online. However, we are friends with several that we have met through parties and clubs. Many of these groups will also operate communities on social media forums that will have a lot of traffic and often more than swinging sites in some areas.
When communicating, just be polite and wait for a response. You will want to come up with a system to try and vet someone once they say that they are interested. Don't wait too long or chat a lot before exchanging face pictures or opening galleries with them. Video chat is a pretty simple way to have an initial conversation and know that you are talking to a real person.
The LS has its own brand of cancel culture. There are many couples who are only looking for a bi female to play with. They want a lady to play with her and she wants her husband to play with her as well. These can be some of the most frustrated couples at clubs and parties if they insist that the husband gets to play. The competition for the unicorns available can be super intense... so much so that the unicorn decides to go for sausage instead of taco that evening. All that to say, don't get too emotionally wound up when sending messages and then when chatting with people in person. Go into this without any expectations and don't get upset when someone politely drifts away from a conversation or says "no, thank you."
There are, however, couples that are fine with the wives playing while the husbands watch and a few other variations of play. Many have found it easier to play with other couples when looking for female bi play than unicorn hunting. You all may consider looking toward couples with similar interests that won't cancel one another out.