Here's a DFSORT job that will do what you asked for:
//S1 EXEC PGM=SORT
//SYSOUT DD SYSOUT=*
//SORTIN DD DSN=... input file (FB/150)
//SORTOUT DD DSN=... output file (FB/150)
//SYSIN DD *
OPTION COPY
INREC IFTHEN=(WHEN=(1,150,SS,EQ,C'IN'),
OVERLAY=(151:SEQNUM,8,ZD)),
IFTHEN=(WHEN=(1,150,SS,EQ,C'REPORT'),OVERLAY=(151:SEQNUM,8,ZD)),
IFTHEN=(WHEN=(1,150,SS,EQ,C'OUTPUT'),OVERLAY=(151:SEQNUM,8,ZD))
OUTFIL INCLUDE=(151,8,ZD,EQ,1),BUILD=(1,150)
/*
For your input example, SORTOUT would have:
sakfhhsfa IN54434
askhdfhsaf REPORT ashf444
ioweuqr237869450 OUTPUT6879777977