i want a bl which the top is okay with being bottom too(and both of them have good mascula...

Not sure if this is exactly what you’re looking for, but in these stories former tops became bottoms.

https://www.mangago.me/read-manga/between_coincidence_and_inevitability/

https://www.mangago.me/read-manga/the_pizza_delivery_man_and_the_gold_palace/

https://www.mangago.me/read-manga/passion_1/

Here it was talked about, but it hasn’t happened yet (and maybe won’t, depends on what the author decides).

https://www.mangago.me/read-manga/our_sunny_days/

https://www.mangago.me/read-manga/playtime_with_hakdo/

thank you but i've read all of them

https://www.mangago.me/read-manga/thirst_1/

thank youuu ♡

Do you want stories where they do switch or stories where the top only (verbally) offers to bottom but never does? (I know more of the former rather than the latter unfortunately).

https://www.mangago.me/read-manga/the_secret_case_files_of_the_cafe_april/
This one is more of a spoiler for the last chapter as it was kinda a surprise, but the seme does offer being the bottom. But the main couple is between this beefy switch and the uke is more like a twink

i want stories which they switch =>

oh thank you so much ♡♡

https://www.mangago.me/read-manga/to_dear_my_sorrow/

https://www.mangago.me/read-manga/wait_a_minute_ore_ga_neko_toka_kiitenai/

https://www.mangago.me/read-manga/neko_x_neko/

https://www.mangago.me/read-manga/better_late_than_never/
(Bara)

https://www.mangago.me/read-manga/yuri_on_ice_dj_d_d_t_daite_dakarete_tokeatte/
(Dj)

https://www.mangago.me/read-manga/seisansei_no_takai_futari_no_seisansei_no_hikui_seikatsu_hypnosis_mic_dj/

https://www.mangago.me/read-manga/papa_naoto_and_papa_tomoyuki/
(Warning: cheating)

https://www.mangago.me/read-manga/nyaa_to_naitara/
(Sexual harassment NOT assault/rape)

https://www.mangago.me/read-manga/usachan_ookami/

https://www.mangago.me/read-manga/metro_dog/ they switch once because the uke was curious and seme is alright with whatever uke likes

https://www.mangago.me/read-manga/life_ain_t_so_bad/ Again, seme is alright with whatever uke likes he just wants to be togetherლ(´ڡ`ლ)
They TRY to switch but uke gets shy so they stop LOL

oh my... thank youuuuuuuuu

Awww thank you so much i liked the story i'll read them immediately♡

Of course! Happy to help! Love to see switching fictionalized and be printed!