How to omit the 'be' verbs
It was confirmed that this change did not cause any impact.

Is it possible to write:
Confirmed that this change did not cause any impact.

??

Question

How to omit the 'be' verbs
It was confirmed that this change did not cause any impact.

Is it possible to write:
Confirmed that this change did not cause any impact.

??

Answer

No.  Change the passive sentence to active, and give the sentence a subject.

Bob confirmed that this change did not cause any impact..
My boss confirmed that this change did not cause any impact.
I confirmed that this change did not cause any impact..

In general, active sentences give you more information with fewer words, so they are usually preferable to passive sentences.

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