The 20-year-old has become a key player for Danny Rohl’s team so far this season.
He is shining in the Championship and got his first senior goal at the weekend in a 2-1 win over Coventry.
"He's probably doing Baz's running," Martin joked to Daily Echo about Charles and Wednesday captain Barry Bannan.
"What is he now, 34? I'm pretty sure Shea has made his job easier.
"He will also give him the ball with a lot of love, care and detail as well. We watched him play against Bristol City and he did some really good things.
"He's learning - and this is why it will be so important for him, rather than being in and around the first team as an option because the Premier League is such a big jump.
"He's there, he's learning and he's playing in really big games. This loan period will be so good for him.
"We are really pleased for him. I'm also very pleased for Barry. Baz is an outstanding footballer, one of the most talented ones I've played with.
"He's still going strong. People like him, Josh Windass, all those guys that have experience will help Shea a lot.
"I hope Shea is enjoying it. Gilly (assistant manager Matt Gill) has spoken to him a fair bit and he seems to be enjoying it. He's got to keep going and keep growing."