Ottoman-Portuguese War / Ottoman Gujarati alliance take Diu in 1538

Just have see that video and mare me wonder what would have happened if the Allie have taken the city and hold it against the portuguese tentative to retake it .
What are the effect on Portugal colonial empire ?
The Ottoman probably become more influent and actif in the Indian Ocean but do they manage to revitalize Mediterranean trade ?

Portugal still has Goa so they will likely be active in the region. The Ottomans would love to go after Goa as well but actual result can differ from success to disaster.

With regards to the Ottoman-Gujarati alliance, it may be like the Ottoman-Adali or Ottoman-Acehnese alliance. Formal alliance but no active support.

The trade to the Meditteranean was still happening even with the Portuguese in the Indian Ocean. This makes attack on Muslim Shipping less likely.
I doubt it would make much of a difference. The Portuguese motivation for developing Diu was pretty much only to use it as a base to disrupt Arabian sea trade with India, which they ultimately failed to do anyway. So, if the Ottomans take Diu in 1538 you may put Portuguese ambitions in Persia and Arabia to an end earlier than IOTL (or maybe not since the Portuguese may still be able to retake Diu in the future or they can build another fort elsewhere nearby), but I don't think the Ottomans would be able to expel the Portuguese from their other enclaves downsouth, and even if they did, it was always possible to get other enclaves. In the end, Portuguese India was simply too spread out and fluid to be overtaken by the Ottomans

That said, perhaps being cut off for Persian and India and their fortunes overall declining in India could lead the Portuguese to turn more towards southeast Asia, which would be interesting....