Top 20 gen 7 Pokemon for number of results on e621.

#1 - midnight form Lycanroc (1130)
#2 - Salazzle (912)
#3 - Primarina (834)
#4 - Incineroar (721)
#5 - Litten (688)
#6 - midday form Lycanroc (589)
#7 - Brionne (483)
#8 - Decidueye (466)
#9 - Popplio (423)
#10 - Rockruff (349)
#11 - Lurantis (308)
#12- Mimikyu (301)
#13 - Tsareena (286)
#14 - Salandit - (282)
#15 - Rowlet (277)
#16 - Pheromosa (220)
#17 - Torracat (216)
#18 - Zeraora (195)
#19 - mudsdale (176)
#20 - Silvally (174)