No evidence given that Macron embraces the Russian point of view on the subject.
Recurring pro-Kremlin disinformation narrative about the annexation of Crimea by Russia and its progressive recognition in the world. No international body recognises the so-called referendum, announced on 27 February 2014, and held on 16 March 2014 amid the presence of Russian troops. The UNGA adopted the resolution 68/262 on the territorial integrity of Ukraine. For the EU statement on the fifth anniversary of Crimea's annexation, see here.
The official transcript of the speech given by Macron in August 2019 at the conference with ambassadors does not mention Crimea apart of the Russian-Ukrainian conflict: "obviously one of the decisive issues to move forward in this direction is our ability to move forward on the Russo-Ukrainian conflict, thus, on the implementation of the Minsk agreements”. Macron also highlighted that "we must be intractable when our sovereignty or that of our partners is threatened".
The borders of Ukraine, including Crimea, were recognised and guaranteed after its independence in 1991 by international agreements, some of which were signed by Russia itself.
Unlike Alsace and Lorraine, regions disputed during the I and II World Wars, the totality of Crimea’s indigenous population was deported under Stalin’s era to Central Asia. The indigenous population started to go back to Crimea quietly during the last years of the USSR and then openly after the collapse of USSR in 1991. Currently, the question of the rights of the indigenous population under Russian occupation is also preoccupying UNESCO. It concerns "disrespect of human rights and fundamental freedoms manifested by Russia since the outset of the occupation of the peninsula". See Russian disinformation narrative on Crimea's history ("Crimea has been always Russian") and its debunking here.
See more disinformation cases on Crimea here.