Roland M-5000 Reference Manual page 198

Channel Link
4.
Press the [SEL] button for the input channel or output bus
you want to assign to the channel link.
The input channel or output bus is assigned to the channel link.
5.
From the parameter list, select the parameters to link.
6.
Tap <OK>.
The input channel or output bus you selected in step 4 is assigned
to the channel link.
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