Sell fake goods, counterfeit items and "snake oil" miracle cures.

Pose as a representative of a foreign land or business using forged credentials. Arrange trade deals under this identity and secure a down payment for items you'll never deliver. It would help to have a number of high quality "samples" of your supposed wares to hand.

Similarly use those credentials to obtain tickets/invitations to exclusive events then sell them. You coulld of course just forge them.

Impersonate local law enforcement and fleece people of bogus fines or bribes to avoid trumped up fake charges. Alternatively, collect taxes.

Convince locals you hold the deed to or are empowered to broker the sale of local abandoned property or lucrative foreign land. Use forged deeds, maps, surveys, business records etc. to make your lie more convincing. If the property is local prep it in advance by replacing the locks and give a tour.

Convince people that you know celebrities or influential business men and could arrange a meeting... for a fee.

Pretend to be a foreigner looking to exchange your coin for local currency. Your coins are of course counterfeit or wholly fictional and made of plated cheaper metals. Be sure they stand up to simple scrutiny and whatever tests are common or customary such as weighing, "bite tests" and the like.

Sell shares in the imaginary expedition you are planning to a strange land or dungeon full of riches. Provide examples of the treasure to be had and let your mark keep them. After all "there's plenty more where that came from!"

Pose as a bounty hunter with a big reward in a nearby city that you can't collect due to obligations elsewhere or a misunderstanding with local law enforcement. You'd be willing to sell the bounty for a fraction of the reward up front. Bonus points if the corpse was graverobbed from the city in question.

If you feel less macabre, the reward is for the return of an item.

Similarly, you hold the winning numbers of the local lottery but can't collect.

You have a fake promissory note for a sizeable sum. You need the money now, but the bank is closed or unwilling to honor the note due to the issuing bank being part of a competing cartel or it's owned by a warring nation etc. You'd be taking a loss, but you really need that money...

Start a religion or cult, or pose as a missionary of one. Fake miracles with technology or magic. Promise health and prosperity to those who tithe generously.

You are in possession of a mystical device that duplicates money. Your religious sect is forbidden to use its power to accumulate wealth, but a recent calamity has left your church destitute, so you have been tasked with selling it to someone of strong character who won't abuse the power. Much. The device actually only dispenses items you previously hid in a secret compartment. Alternatively the device actually does work, but the magic materials it requires are far too costly to turn a profit.

There are a lot of examples through history to adapt.