This is quite interesting, I just noticed recently that Natalie.mu has been publishing sales ranking from two different sources for a while now on their Comic page, though they are completely devoid of actual sales. As such, we get to see only the ranks. This Friday, Oricon will be releasing the Top 30 Manga sold on their site, thus I figured it will be cool if we could see them side by side. Once Oricon has released their chart, I shall be updating the list here, and indicate whether if they are equally represented or the other way round.
Anyways, you can find the information via Natalie here. Before you check out the list below, the sources mentioned above are from TSUTAYA and COMIC ZIN. You can click on the bold purple links provided down below to be redirected to their sites. See what they are like. Remember, the data you see down below are all thanks to all the three entities listed above!

TSUTAYA
1. SPY×FAMILY Vol. 5 [MATCHED]
2. Boku no Hero Academia Vol. 28 [MATCHED]
3. One Punch-Man Vol. 22 [MATCHED]
4. Dr. STONE Vol. 17 [MATCHED]
5. Boruto: Naruto Next Generations Vol. 12 [MATCHED]
6. MF Ghost Vol. 19 [MATCHED]
7. Jigokuraku Vol. 11 [MISSED] [RANK 9]
8. Kinnikuman Vol. 72 [MATCHED]
9. Kekkai Sensen: Back 2 Back Vol. 8 [MISSED] [RANK 7]
10. TV Anime Kimetsu no Yaiba Official Characters Book Vol. 1 [MISSED] [UNRANKED]
*Note on the right is the comparison to Oricon sales chart for the same period.

COMIC ZIN
1. NEW GAME! Vol. 11 [MISSED] [UNRANKED]
2. SPY×FAMILY Vol. 5 [MISSED] [RANKED 1]
3. Yuyushiki Vol. 11 [MISSED] [UNRANKED]
4. 2.5-jigen no Yuuwaku Vol. 6 [MISSED] [UNRANKED]
5. One Punch-Man Vol. 22 [MISSED] [RANKED 3]
6. Heterogenia Linguistic: Ishuzoku Gengogaku Nyuumon Vol. 3 [MISSED] [UNRANKED]
7. Ramen Daisuki Koizumi-san Vol. 9 [MISSED] [UNRANKED]
8. Kekkai Sensen: Back 2 Back Vol. 8 [MISSED] [RANKED 7]
9. Tonari no Kyuuketsuki-san Vol. 7 [MISSED] [UNRANKED]
10. Watari Tori to Katatsumuri Vol. 1 [MISSED] [UNRANKED]
*Note on the right is the comparison to Oricon sales chart for the same period.
In my opinion, the upcoming Oricon chart will more likely be a lot closer to the one published by Tsutaya. SPY×FAMILY has been gaining traction for some time now in Japan and I expect it to sell above 350,000 copies – basing my prediction based on previous sales. Boku no Hero Academia is no small fry at all, my prediction, 250,000 copies. One Punch Man may hang around the 150,000 copies mark. What about you guys? Any thoughts?
Source: Natalie.mu
Updated (September 15, 2020): Added comparison to Oricon sales chart.
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