It looks like the egg jelly of a moon snail, one of the Polinices sp. You can see spots inside which are likely to be the eggs. It is unusual for the jelly to be coloured but maybe that is just the background showing through?
Yes, I think you're right. This is what I found...There are two species in the genus: Physalia physalis (known as Portuguese man-of-war) in the Atlantic, and Physalia utriculus (known as bluebottle) in the Indo-Pacific. (Source: https://dan.org/health-medicine/health-resources/diseases-conditions/portuguese-man-of-war-bluebottle/#:~:text=There%20are%20two%20species%20in,)%20in%20the%20Indo%2DPacific).
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