Kate and Meghan
Kate Middleton beats Meghan Markle in being the most influential royal in style. Pictured: Middleton and Markle attend day twelve of the Wimbledon Lawn Tennis Championships at All England Lawn Tennis and Croquet Club on July 14, 2018 in London. Getty Images/Clive Mason

Kate Middleton is the most influential royal when it comes to fashion.

The Duchess of Cambridge and Duchess of Sussex are often compared when it comes to their styles. However, according to a new study, Middleton effect is more powerful than Meghan Markle effect.

Evening Standard reported that Middleton beat the former "Suits" star as this year's top royal style influencer. Middleton has a big impact on the public's shopping habits based on eBay's annual UK Retail Reports.

Middleton's maternity style generated more online searches in the e-commerce website than any other royal over the past year. The report noted that searches for tailored maternity coats more than tripled and searches for Jenny Packham, one of Middleton's favorite designers, have more than doubled following the sighting of Duchess of Cambridge's in a red Packham smock dress for Prince Louis' public debut.

"While Meghan was clearly the focus of the fashion pages this year, Kate's distinctive style has long been a hit with shoppers on eBay since her wedding in 2011," said Rob Hattrell, UK vice president of eBay.

"We always see an uptick in searches around landmark royal events and 2018 was a bumper year for small businesses on eBay, with both the birth of Prince Louis and Meghan and Harry's wedding driving purchases across the nation.."

On the other hand, Markle came close to her sister-in-law. Her Givenchy dress during her wedding day increased the searches for that designer by more than 60 percent. The Duchess of Sussex's halter-neck evening wedding dress also doubled the searches for that particular brand.

Meanwhile, Markle surpassed Middleton in Lyst's 2017 The Year in Fashion roundup. Prince Harry's wife landed on the fourth spot while Prince William's spouse lagged behind in the fifth.

"Meghan proved her royal style credentials this year, wearing heritage British brands Barbour, Hunter and Burberry," the site said. "She also spiked searches for lesser known labels Misha Nonoo and Finlay and Co."

Lyst also recognized the Middleton effect. According to the publication, the Duchess of Cambridge "continues to spark global demand for her looks- this year caused dresses by Erdem, L.K. Bennett, Roland Mouret and Dolce & Gabbana to sell out in seconds."