I know that when things are normal, there is at least one local group in Machynlleth that gets together each week to chat in Welsh. I don’t know whether they are doing so at the moment, even when lockdown ends. Our local Dolgellau chat group are meeting via a Skype group.
There is also the Welsh Slack where people arrange online chats, either one-to-one or in groups. I quote from the introductory message: " If you would like to become a member of the Slack WSP community, you need to be ‘invited’ to the group - to do this you simply send an email to admin@saysomethingin.com with WSP in the title and you’ll be sent an invite." Details here…