I didn't know you wanted the pokeball to go away.
I'll write it again.
First event:
If switch pok2 is on
>Move Event: This Event, Change Graphic(Change Graphic into a transparent charaset)
Else
>If switch pok3 is on
>>Move Event: This Event, Change Graphic(Change Graphic into a transparent charaset)
>else
>>Change party member: Add pok1
>>Switch pok1 on
Second Event:
If switch pok1 is on
>Move Event: This Event, Change Graphic(Change Graphic into a transparent charaset)
Else
>If switch pok3 is on
>>Move Event: This Event, Change Graphic(Change Graphic into a transparent charaset)
>else
>>Change party member: Add pok2
>>Switch pok2 on
Third Event:
If switch pok1 is on
>Message: Move Event: This Event, Change Graphic(Change Graphic into a transparent charaset)
Else
>If switch pok2 is on
>>Message: Move Event: This Event, Change Graphic(Change Graphic into a transparent charaset)
>else
>>Change party member: Add pok3
>>Switch pok3 on