To clarify a point, though the Ministry of Trade issue one such requirement for e-commerce, it's not a done deal. Many lawyers think the decision itself was not legal, and insist that there is no legal basis for banning or restricting LGBT content in Turkey.
Here's an article discussing the legal situation in light of Riot's "colour festival" precaution in Turkish. Google Translate will probably offer a decent translation, but I'll translate the key part myself, where a practising lawyer gives a rundown of the current situation:
"Here's what we should look at: (...) Of course, there are no laws in Turkey making it necessary to refer to rainbows as "colour festival", or that bans video games from using LGBTI+ imagery. As a result, the statements that the company did this to "comply with local laws" or "localise" the content all belie the fact that this was the company's decision. There are no laws that would force the company to take these steps. If there were any compelling norms to this effect, the company would mention them in their statements. Then we could ask: Does the referred law really ban commemorating 17 May [International Day Against Homophobia, Biphobia, Interphobia and Transphobia] or Pride Week? Does it ban the use of rainbow flags? Does it force the apolotisation of an expression symbolising LGBTI+ people in the form of 'colour festival'? The company's statement refers to no such law."
"So why might have they done this? They probably acted in light of the homophobic decision taken by the Advertisement Board of the Ministry of Trade (...). The decision was: 'Rainbow-themed goods in e-commerce hurt children's moral development. So websites that sell such goods must place a +18 disclaimer on such goods.' But I'll reiterate, (...) this decision has no legal ground. It was a decision taken with no basis on Turkish Trade Law or Law On Consumer Protection, or any other law. (...) The company probably felt the pressure of this LGBTI+-phobic atmosphere and took this decision even though there is no legal requirement for them to do so. This isn't a problem only for LGBTI+ people in Turkey, it's a matter that concerns LGBTI+ players of this game no matter where they live. Let me say that again, there is no law in Turkey that forces companies to take these decisions."
So while I am not a lawyer, I can say that there are at least some legal experts that argue that there is no legal problem with providing pride-themed products in Turkey.