Hello @Fide,
It depends if the respective pinctrl is used by another node.
If not, the pins will remain in their default state.
If yes, it will be configured as an input, unless the node’s driver configures in in another way.
In this specific example, it is SPI, so if the pinctrl is used by a node for an SPI instance the driver may reconfigure the input buffer.
Regardless, it would be a best practice to disable the SPI node which uses pinctrl_spi2 if these pins are left unconnected.
Best Regards,