Learn English – The word for “professional system” or “task system”

Strategy often goes down well these days.

The OP hasn't explained why the term multipurpose is not appropriate for their needs, it seems a perfectly appropriate expression to describe any object that has more than one function.

There are; however, viable alternatives. I suggest: multifunctional and all-purpose

• something that is multifunctional does several different things or has several different uses
  e.g. a multifunctional tool

• able to be used in a lot of different ways
  e.g. an all-purpose stain remover

(Source: Macmillan)

A multifunctional piece of furniture: study desk/table/seat

EDIT

Thanks to @displayName who has pointed out that the OP needs this word for a software product. That type of clarification should be made or edited in the post, and not left in the comment section.

“Multifunctional software” produces over 200 hits in Google Books

In today's world of increasingly integrated and multifunctional software programs, it seems particularly important to theorize and empirically examine the relationship between task and technology in the formation and influence of CSE.

_{Human-computer Interaction and Management Information Systems
^{By Yahong Zhang, Dennis F. Galletta}}

“All-purpose software” produces fewer than seventy hits on Google books

Today, all-purpose software for microprocessors and other software tools determine technical progress in most fields …
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