Chase Herro is an online salesman who proudly calls himself a “dirtbag of the internet,” able to sell anything to anyone. Zachary Folkman ran a company called Date Hotter Girls, offering advice under a pseudonym on how to pick up women at bars.

For the past decade or so, the two men have been serial entrepreneurs, leaving behind a trail of lawsuits and unpaid debt and taxes.

Now they are former President Donald J. Trump’s business partners.

Mr. Herro and Mr. Folkman are the forces behind World Liberty Financial, a cryptocurrency venture that Mr. Trump and his three sons announced on a livestream last month. The Republican presidential candidate declared his new enterprise would help turn the United States into “the crypto capital of the world.”

His eldest son, Donald Trump Jr., said Mr. Herro and Mr. Folkman would help engineer a financial revolution based on digital dollars. “You could put them in a boardroom at Goldman Sachs, and they’re going to smoke the people in the room,” he said.

Other crypto experts have expressed doubt, even alarm, about the business, the former president’s involvement and his partners. Eswar Prasad, an economics professor at Cornell University, said Mr. Herro and Mr. Folkman did not appear to have the technical or financial savvy to make the venture work.

The concept behind it, which was pitched as groundbreaking, seemed similar to other existing crypto ventures, said John Reed Stark, a former senior official with the Securities and Exchange Commission.

“It’s a bunch of nonsense, and a terrible opportunity for investors,” he said.

For Mr. Trump, the project is part of an extraordinary effort to mix his personal finances with his bid to return to political power. Mr. Trump campaigns daily on a social platform owned by the Trump Media & Technology Group. Since he announced his new election effort, he has sold silver coins, Bibles, gold hightop sneakers, digital trading cards and, as of last week, diamond-encrusted watches, all branded with his name, image or campaign themes.

Like his social media company, his new crypto business stands out for its potential conflicts of interest. If Mr. Trump is elected, he would be in a position to influence the regulations that could determine whether World Liberty Financial succeeds or fails. Mr. Trump has already said he opposes strict federal intervention in the industry, which now operates in a legal gray area.

Even the project’s leaders sounded a little incredulous that the presidential candidate was jumping into a partnership with two little-known 39-year-olds in a high-risk industry just before Election Day.

“If you would have thought six months ago that Donald Trump is dropping a decentralized finance project, would anyone have believed it?” Mr. Folkman asked on the livestream announcing the project. Especially, the event’s moderator added, “with two crypto punks.”

A Trump campaign spokesman did not respond to a request for comment. Asked about the company’s plans, Jim Redner, who was hired in September as World Liberty Financial’s spokesman, said he had just quit. Mr. Herro, Mr. Folkman and World Liberty Financial did not respond to requests for comment.

Trump’s Evolution

As recently as 2021, Mr. Trump himself said crypto “seems like a scam.” The F.B.I. has said it is riddled with pervasive fraud that cost Americans billions of dollars last year alone.

But Mr. Trump’s views started to change, he said last month, after he discussed the technology with his sons, who were enthusiastic about its potential.

World Liberty Financial first took shape about nine months ago, when Mr. Herro and Mr. Folkman were connected to the Trump family through Steve Witkoff, a real estate developer, and his son, Zachary, an investor in crypto projects.

Mr. Witkoff is a close friend of Mr. Trump’s and a donor to a pro-Trump political action committee. He testified for Mr. Trump in the former president’s civil fraud trial in New York this year, and was playing golf with Mr. Trump during the latest attempt on the former president’s life.

Mr. Witkoff is no crypto expert — he mispronounces the word “memecoin,” a type of digital currency, as “me me coin,” according to a person who requested anonymity to describe a private conversation. But he believed the project would be good for the youngest Trump son, Barron, an 18-year-old college freshman, giving him business experience and steering him away from more scam-ridden segments of the crypto industry, the person said.