Soto hit a home run off Gerrit Cole, drove in three runs and stole a base in a 5-4 win for the Nationals at Minute Maid Park on Tuesday.
Nationals manager Hinch was not surprised to see the 20-year-old make a big impact on his World Series debut.
"I don't even look at him as young until you see his face," Hinch said of Soto. "He's got kind of the 'it factor'.
"He's got the twitch. He's got fast hands. He's got no fear, he's mature. Don't let the age fool you."
Washington pitcher Max Scherzer felt it was a collective effort that got the Nationals off to a winning start in the best-of-seven series.
"This is just a team win," Scherzer said. "When you look at this, there wasn't one guy that won this game.
"It was a collection of everybody and up and down the line-up, in the bullpen, what can you say? The reason we won today was because of everybody in this clubhouse."
Astros outfielder George Springer set a record by hitting a home run in five consecutive World Series games, but said that was no real consolation.
"I'd rather win," said Springer. "I mean, cool. Great. It's an honor ... but no doubt about it. I'd rather win."