Okujima Hiromasa, Takahashi Hidebu, Est Em, Okadaya Tetuzoh, Asada Nemui, Totempole, Kajimoto Reika, Mentaiko (geicomi dj mangaka influenced by famous shounen/seinen stories), Iwasawa Midori, KOIKE Sadaji, ARAI Niboshiko, etc (the space here is limited, so no more creator names)
Also:
https://www.reddit.com/r/Animesuggest/comments/17vufpd/are_there_any_shounen_manga_with_bl/?rdt=44199&onetap_auto=trueA very good list from RoseMary:
https://www.mangago.me/home/mangalist/226060/?filt 
