Hi.
I would set the fader and set text in a seprate fsm on a empty game object called Ui Handler.
The Ui handler could be set as a global if you need to access it with prefabs or cross scenes.
So on that fsm :
Start state : just a empty state that does nothing (i usually call it 'Idle')
State 2 :
have a Global Transition (cal it "Show Text" for example)
Then :
Set Text Action
then fader action(s)
and connected direction to the text object.
Then possibly do a set text with no text in it to clear the text but that might not be necessary.
Then on post sings when selected :
State 1 :
Set Fsm Text
Then Send Event (by Name) and send "Show Text" on the Ui handler object.
If you can connect to the 'Ui handler Directly and you wont use spawned prefabs to communicate with it or cross scene (meaning multiple scenes active and something from another scene needs to access the Ui handler)
Then don't use a global variable.
you should always try to minimize using global variables.
Here's a video about Global events / transitions :