In order for a business to have a permanent establishment in country A it has to register a branch there and carry on business there. If the business is buying and selling financial instruments on international exchanges via a company registered in Switzerland and a stock broker registered in the US, article 7 won't apply for Hungary.
Why do you think in the DTA between CH and HU they differentiated between a place of management and a branch?
![4SbXl8.jpg](/proxy.php?image=https%3A%2F%2Fi.snipboard.io%2F4SbXl8.jpg&hash=fcd6b351994e413965f6e260a7b5edcd)
Because you can have a place of management without a branch so a PE could be created even without registering a branch.
Also it's in OP best interest to create a PE in Hungary because HU levies 9% taxes instead of ~12% (depending in which canton the company is formed) in CH.
No dividends but wouldn't the DTA apply to regular business income too?
DTA only applies to dividends, interest and royalties.