Ankara decided to join the so-called “Crimean platform” and conclude an alliance with Kyiv. (…) Turkey now intends to take Crimea under its sovereignty.
This is a pro-Kremlin disinformation narrative about the occupation of Crimea.
During the official visit of President of Ukraine Volodymyr Zelenskyy to Turkey on October 16, the joint statement of the leaders of Ukraine and Turkey was issued. The statement, signed by the two leaders, declares that “the Republic of Turkey reaffirms its unconditional support for Ukraine's sovereignty and territorial integrity within internationally recognised borders and welcomes the cooperation within the Crimean Platform initiated by Ukraine.”
There is no mention that Crimea will be placed under Turkish sovereignty.
The Crimean Platform is an initiative of the Ukrainian government in order to keep the occupation of Crimea in the focus of international attention.
See the similar case, "Turkey considers Crimea to be Turkish".