If this system is advising that you require a visa when adding a Swiss employee, this is likely due to the Swiss nationality not being ticked as an EEA nationality. Although Switzerland is not part of the EEA, they are part of the single market, which means Swiss nationals have the same rights to live and work in the UK as other EEA nationals.
Any updates regarding Swiss or EU/EEA nationals' rights to work within the UK will be found on the UK Government's website.
To change the nationality settings for swiss nationals so they can be added without visa information in the Access People Hospitality HR system you will need to follow the below steps:
Navigate to Settings within the menu structure.
Expand the Module Settings drop down then expand the General drop down menu.
Select Nationality then search for Swiss in the description field and click on the result.
Ensure the European Economic Area check box is selected.
Click Save.