Updated: Mar 2
Venom came into the Korean market in 2018 and from research, it made hit sales of about 6.5 billion. Directed by Reuben Fleischer with Tom Hardy as Eddie Brock and Venom comparing it to Venom: Let There Be Carnage which was directed by Andy Serkis was recently released into the Korean market in terms of sales, the pandemic played its role in the sales of Venom surpassing the sales of Venom: Let There Be Carnage.
Source: https://www.koreamovie.net/movieintelligence 10/22/2021
Venom slowly faded from the Korean market in 2018 and Venom: Let There Be Carnage entered with about 1.96B on the 13th of October and sales have reduced to 417.8 million approximately. We can't really conclude about the Venom with the highest sales because Venom: Let There Be Carnage can re-enter the Korean market with higher sales but for now it is safe to say Venom made more sales entering the Korean movie market.