Thread: как бы ни был

Originally Posted by Antonio1986

кто бы мой собеседник ни будет.

Okay, first, the particle БЫ there suggests that you use the past tense verb, so it should have been был
Second, don't forget about declensions, быть КЕМ?, and not быть КТО.

So given that the whole phrase should have been:

Кем бы мой собеседник ни был...

But you're on the right track here, it's just some grammar mistakes