
Shirou would outshine everyone if Fate collabs included him more often. Hes literally the Goku of Fate.
Lets be honest Shirou is most of the time not included seriously in collab for a reason. It seem Type moon and Nasu does not want him to be in anything serious, anytime he appears he just steal the show and even with Saber. If you bring Shirou in a collab Saber would be outshined like fuck and Type moon wants to hype saber as some kind of top tier waifu.
Shirou is the cool OG fate protagonist, you cant just put him in a game and be like hes not 6 stars for example.
For me Nasu is making sure Shirou character doesnt write himself in other works. So he put Archer who is already a completed character as replacement.