Flashing Light or Visual Signaling Certification

No. But you are welcome to use “flashing lights” as long as you want in the Engine Room.
Norway requested that the whole Morse Code thing should be abolished for Deck Officers long time ago.

I’m glad to learn that apparently I don’t need Flashing Light.

While Flashing Light has been obsolete for decades and a waste of time, it’s interesting that this is another area where the adoption of STCW lowered US maritime standards.

I don’t think that’s the case here. Flashing light was only required in recent years because of STCW, otherwise the USCG would have probably dropped the requirement. When STCW revised the requirement in 2010 then the USCG revised it to match.