France won the first Test in Toyota 42-23 after scoring four tries in the second half, stretching away after a spirited Japan had held them 13-13 at the interval.
New Zealander Joseph said his team would not abandon their dynamic passing game at Tokyo's National Stadium on Saturday, but called for his players to find the "control" that escaped them last week.
"We've just got to get a bit of balance into our game and make sure that we don't try to change our game," he said.
"That's the way we play the game of rugby but we've just got to be a little bit smarter when we have the ball."
Joseph said Japan had "started overplaying at times" and struggled to cope with the heat in steamy Toyota, which soared to 33 degrees Celsius at kick-off.
Cooler temperatures are forecast for Saturday in Tokyo and Joseph was able to welcome back two players who missed last week's game after testing positive for Covid.Scrum-half Naoto Saito returns to the starting line-up while World Cup veteran hooker Shota Horie was named on the bench.
Joseph shuffled his lock forwards but kept faith at fly-half with the inexperienced Seungshin Lee.
The 21-year-old won only his second cap last week after being drafted in the day before the game when Takuya Yamasawa tested positive for the virus.
"We think he's got a lot of potential," Joseph said.
"Giving him another opportunity on the back end of last week is only going to see Lee become a better player faster."
Japan have not beaten a top-tier team since stunning Ireland and Scotland at the 2019 World Cup, where they reached the quarter-finals as hosts.
France are looking to win their 10th straight Test and Joseph said they will be "very strong" despite bringing an inexperienced squad to Japan.
"They have powerful runners coming through and if they get momentum they're very hard to stop, which is what they proved last week," he said.
Japan (15-1): Ryohei Yamanaka; Gerhard van den Heever, Dylan Riley, Shogo Nakano, Siosaia Fifita; Seungshin Lee, Naoto Saito; Jack Cornelsen, Ben Gunter, Michael Leitch; Sanaila Waqa, Warner Dearns; Asaeli Ai Valu, Atsushi Sakate (capt), Keita Inagaki
Replacements: Shota Horie, Yukio Morikawa, Yusuke Kizu, Takayasu Tsuji, Tevita Tatafu, Kaito Shigeno, Yu Tamura, Shane Gates