Can I use 1 EMC filter in the input power supply connection for multiple drivers/controllers?

EMC Filter used for noise suppression on multiple motion control axes

It is recommended to install the EMC filter as close to the driver as possible, this is to ensure the best possible electrical noise suppression. The required current to power multiple drivers at once may overload the EMC filter when passing through as well. Due to these reasons, it is recommended to have a 1:1 EMC filter to driver ratio.