You were half right, I'd imagine this lot will become a new party be the end of the year:
https://www.propel.wales/ McEvoy will be out of Plaid soon and one of the other speakers, Gwyn Hopkins, was suspended by Plaid
In terms of the party's ideology, who knows? I did a week's work experience with McEvoy and nothing from him or his staff indicated right wing tendencies, he even gave me a list of books he suggested me to read with included Homage to Catalonia & works by Marx & Engels
Saying that, the bloke's an opportunist, so who knows?