Josh Porebski and Trent Rippey were the only other New Zealand boat to qualify for the medal race, which was a decent accomplishment given their poor start to the regatta, and promising combination Olivia Mackay and Micah Wilkinson sailed a consistent regatta in the Nacra 17 to finish 13th overall.
McHardie and Wilkinson now switch their attentions to June's Red Bull Youth America's Cup in Bermuda, with the NZL Sailing Team hoping to replicate the achievements of the 2013 team headed by Peter Burling and Blair Tuke who won the inaugural Youth America's Cup.
Meech and Andrew McKenzie head to Croatia to train at the venue for this year's Laser world championships in September. McKenzie will also compete at the Delta Lloyd regatta in the Netherlands later this month.
Meech, who underwent knee surgery in December, was the only Kiwi in action in France overnight. Olympic champion Tom Burton from Australia won the medal race but Cypriot Pavlos Kontides claimed gold on countback from Italy's Francesco Marrai after finishing second in the double points medal race.
"I was happy with how his day went," Meech said. "I was really trying to win the race but just couldn't quite get it right coming down the first run. I needed to come second to move up to eighth, which was the best I could have hoped to finish in the regatta going into the last race."
Olympic 49erFX silver medallists Alex Maloney and Molly Meech will compete in next month's Sailing World Cup final in Santander, Spain.
New Zealand results after the final day of the World Cup regatta in Hyeres, France, overnight (NZT)
Laser (out of 60)
9th - Sam Meech 26 6 1 14 30 19 28 (34) 5 6 6 - 141 points
15th - Andrew McKenzie
49er (out of 28)
10th Josh Porebski and Trent Rippey
16th - Isaac McHardie and William Mckenzie
Nacra 17 (out of 29)
13th - Olivia Mackay and Micah Wilkinson
Finn (out of 34)
29th - Brendan McCarty