Topic in config file

[meccip]

Hello,

I have this in config file
[GSdata]
protocol=PI17
port=/dev/hidraw0
baud=2400
command=GS
outputs=json_mqtt

[workmode]
protocol=PI18
port=/dev/hidraw0
baund=2400
command=MOD
outputs=json_mqtt

Mqtt data is sent to nodered with topic mpp-solar
first sent >> mpp-solar {"GS data"}
second sent >> mpp-solar {"MOD data"}

my question is how can I change topic name inside config file ?
for example
first sent >> topic1 {"GS data"}
second sent >> topic2 {"MOD data"}

Thank you

[meccip]

if nobody answer I use a different way

I use a tag name in config and outputs=tag_mqtt
and I made an extra function in nodered for json