I am about to get a second dog and I was recommended by a trainer to train the second dog in a different language in order to avoid command conflicts. I would like to know how do you guys feel about it?

I think the trainer who gave you this advice lacks experience in dog training. Train the dog in English and use the dog’s name before each command. I.E. Fido Come. Using the dog’s name before a command makes it very clear who you are talking to.

A perfect comparison would be if you had several brothers and sisters. Your parents didn’t need to teach each child with a different language did they?

Regards,
Ed Frawley