*Club domestic league appearances and goals, correct as of 15:38, 3 April 2024 (UTC) ‡ National team caps and goals, correct as of 14:47, 20 November 2023 (UTC)
Stoychev began his career in the local FC Dragoman at the age of 11, before moving to Septemvri Sofia academy in 2018. He made his professional debut for the club in 2020 on his 17th birthday, in a league match against Litex Lovech.[2] On 17 October 2022, in a league match against Levski Sofia, he received an injury that ruled him out until end of the season.[3] Ironically, before this, Levski had contacted him and expressed a desire to sign him during the winter break, but the transfer failed.[4] After Septemvri were relegated to the Second League, in July 2023 he signed a year-long loan deal with First League team Arda Kardzhali.[5]