Would there be no difference? In 1453 otl the Ottoman Empire is ascendant and presided over most of the Balkans and Anatolia. If the Roman Empire is weaker than the ottomans otl there would already be a difference in trade as the Italian city-states would have different trade patterns with the Ottomans. Venice for one would be either stomped out of existence or have their power significantly reduced, while Genoa would either have more trade as an ally of the Rhomans or be pushed out of the Eastern med by the 15th century as the Rhomans would want control over the Eastern med. These factors mean that the Eastern Med is very different than otl, and as a result products from Anatolia would be very different than otl.This Byzantine'(which by 1453 could at most become a decent medium power)s impact on Mediterranean trade would not cause any meaningful difference to the Hundred Years War.
The Rhoman empire’s existence also means that Egypt would be directly trading with the European powers not through the Ottoman Empire (spices). This means Egypt takes a larger cut, which means either the spices are cheaper or they are more expensive. The lack of a powerful nation that protects the merchants of the sea (especially Muslim) also means that more pirates of various stripes would be more prolific. The presence of an Orthodox power where they were Muslim trade routes otl means that a lot of routes would be different.
Tl:dr: Nova Roma and the Ottoman Empire are very different countries with different circumstances.