Which spices exactly are replaced by the mustard fenugreek masala?

You would use a premade masala blend to replace the cinnamon, cloves, and fenugreek seeds. Garam masala, for example, would be ok here.

Unclear on your question.
Do you want to replace the masala in this mac and cheese recipe?
If yes, keep the last four ingredients (cheeses, salt, pasta) and replace all others with a butter (curry) sauce usually used for chicken.