Switzerland's upcoming vote on how to create money is intellectually challenging for the traditional banking system, an economist told CNBC on Friday.

The wealthy nation is due to vote Sunday on whether it should have a so-called sovereign money system — meaning the central bank would be the only provider of Swiss francs. In other words, commercial banks would no longer be able to create cash; their ability to lend money would be restricted.

Supporters of the initiative argue that the potential change would make the system less dangerous to credit risks. They use the 2008 global financial crash as an example of why the banking system needs to reduce irresponsible spending. Opponents, such as UBS Chief Executive Officer Sergio Ermotti argue that approving the initiative would be "suicidal."

"For us, it's actually a really intellectual challenging exercise. What you just mentioned… would effectively prevent the commercial banking sector from running money multipliers, from lending out to the economy and creating deposits," Evelyn Herrmann, European economist at Bank of America Merrill Lynch, told CNBC's "Squawk Box Friday."