Stax, 9 bytes

éÅ╘t«╢£à9

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Stax, (削除) 9 (削除ここまで) 8 bytes

åτIns↓μg

Run and debug it

Explanation (unpacked):

M{c0-u=}j Full program, implicit input
 e.g. ["Programming", "Puzzles", "Code", "Golf"]
M Transpose
 ["PPCG", "ruoo", "ozdl", "gzef", "rl0円0円", "ae0円0円", "ms0円0円", "m0円0円0円", "i0円0円0円", "n0円0円0円", "g0円0円0円"]
 { }j Find first matching element:
 e.g. "PPCG"
 c0- Copy and remove zero bytes (padding)
 "PPCG" "PPCG"
 u Unique
 "PPCG" "PCG"
 = Check if equal:
 1
 First matching here: "ozdl". If none is found, the stack is empty
 Implicit output if anything on stack