Code:
on *:TEXT:*:#firstchannel:{
  if $network == firstnetwork { scid -at1 relay $unsafe($chan $1-) }
}

alias -l relay {
  if $network == secondnetwork && $me ison #secondchannel {
    msg #secondchannel ( $1 ) $2-
  }
}
replace #firstchannel, firstnetwork, secondchannel and secondnetwork accordingly

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