Yamamoto's Zanka no Tachi (Bleach) is a blade of compressed and solidified flames.
Shuren (Bleach) compressing flames into solid blades and lances.
Linda Littletrees/Witch Woman (Marvel Comics)
Mui (Naruto) using Heavenly Prison Fire Sword to solidify flames into a sword.
Portgas D. Ace (One Piece) using Higan to fire bullets of hardened flame ...
... and Shinka: Shiranui to solidify flames into spears.
Caesar Clown (One Piece) concentrating oxygen and igniting it to form his Blue Sword.
Hiei's (Yu Yu Hakusho) "Dragon of Darkness Flame" takes on solid form that causes tremendous solid impact.
Burnishes, humans mutated by connection with flame-based inter-dimensional entities called Promare such as Lio Foltia (Promare) are endowed with ability not only to create and manipulate flames, but also shaped it into solid constructs such as a motorbike...
...or armor and weapon.
Choi Jong-In (Solo Leveling) creating and solidifying his Flame Spears...
...and Flame Prison, a powerful barrier of flames.