I remember moves well up until generation 7 and over. For example, I don't remember the signature moves of Dhelmise, the Tapu guardian deities, Togedemaru, and Silvally because I never ended up using them in the Alola Region. I do remember the signature moves of the Alolan starters, Lurantis, Bruxish, Tsareena, and Palossand because I used them in my party. I read through the descriptions if I don't recognize a move.
It's sad not all Pokemon moves have made the transition to the Switch games. I miss having Psycho Boost on Deoxys and the XD: Gale of Darkness Lugia. I miss being able to bring up the Dizzy Punch Odd Egg hatchlings from Virtual Console Pokemon Crystal. I miss Delcatty having Assist and Vespiquen having Heal Order, which were originally signature moves. :(