Display Variables on Specific Task

Hello 

I want to show specific variables on the Catalog Task, The variable should be hidden for another task and RITM  in workflow, had a generic solution based on a Onload client script -short description Which I don't want to proceed 

The variable should become mandatory when we try to close the task with the ui action "Close Task"

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Please suggest some good solution 

@Ankur Bawiskar @Voona Rohila