Joshua Matthews is not related to Riley in this story, they just both have the last name because it's a common lasts name.
Maya is the same person that she was in 7th and 8th grade. She got over Lucas because he chose Riley. Which helped her realize, that she didn't want to be in a couples relationship with him, she just wanted to be friends forever with him, riley and Farkle. And so she has never met or had a crush on him. But she's heard of him. He's a artist just like maya but she still never bothered to meet him.
Josh is the same character as in the show, caring, sweet, great style and a great sense of humour. Although he does have his flaws, and he's always ready to beat someone up if he has to. He's into art. He's heard of Maya as the rebellious chic. He's never met her, nor does he want to, but he heard she likes art too.