Tomb....dont know if there is an interference free trolling motor.
This is because of so many variables or conditions between each.
Factors such as construction, voltage (amps), positioning, wiring, grounding, shielding or chokes (installed or added).
You might take some time and search this forum on the subject. There are many postings on this issue....
As well as a lot of experienced guys who have gone thru the issue and with some posting fixes...
There is a search area at the top of the main menu. Be creative with the search arguments and possibly use several attempts to find the postings..
Once you select a topic you will find related posting below the returned post. Those may contain information pertinent also..
Chuck