nana

http://www.mangago.me/read-manga/beast_feast/
http://www.mangago.me/read-manga/heart_strings/
http://www.mangago.me/read-manga/sugar_code/
http://www.mangago.me/read-manga/houkago_no_love_call/
http://www.mangago.me/read-manga/koi_made_hyakurin/
http://www.mangago.me/read-manga/kyou_hana_no_gotoshi/
http://www.mangago.me/read-manga/koi_to_wana/
http://www.mangago.me/read-manga/ake_nure_goyou_ni_furu_yuki_wa/
http://www.mangago.me/read-manga/gokudou_darling/
http://www.mangago.me/read-manga/before_daylight_love/
http://www.mangago.me/read-manga/crossover_love/
http://www.mangago.me/read-manga/tight_rope/
http://www.mangago.me/read-manga/1_en_no_otoko/
http://www.mangago.me/read-manga/usagi_otoko_tora_otoko/

Wow you asked something that I was about to ask lol

Bi No Isu
Totally Captivated
Viewfinder
Ikoku Irokoi Romantan
Kobi No Kyojin
Beast & Feast
Aiso Tsukashi
Leopard Hakuso
etc

1. Sorry dunno.
2. I believe it's just an illustration from Kyuugou. I remember seeing a compilation of different sex positions drawn by different mangaka.

Thank you

For number 1, I think there's no translation yet.
https://www.mangaupdates.com/series.html?id=91874

Second is from here
https://myanimelist.net/manga/48435/BLT48
It's a book by different mangaka for illustrating different sex positions ;)
https://www.google.co.uk/amp/s/hazukashiikedo.wordpress.com/2012/09/19/blt48/amp/

Boy, do I want that hard copy for my own reference ლ(´ڡ`ლ)

Same here ;)