No, the slang works for I hear ya, but it isn’t used as I listen ya.

I agree with Bill, but people do also use hear to mean they understand what someone has said and sometimes for understanding their point of view as well. It may not be correct, but it’s not uncommon.

tajen literally it means ‘I can hear you’ but the general meaning is ‘I understand the point you’re making’

"I hear you" can sometimes mean "I understand the point you are trying to make."

It can mean friendly agreement. I can say "I'm tired of this cold weather." A friend might answer with one of several idiomatic phrases. "You can say that again!" Or, "You speak truth." Or, "I hear you."

In a discussion, it can mean "Stop saying that over and over. I don't agree with you, but I did listen to you."

For example, talking to my supervisor, a conversation might go:

Me: "I need a faster computer."

Boss: "Well, you have a good computer."

Me: "It takes over fifteen minutes to compile the current build."

Boss: "Well, the budget is tight right now."

Me: "But I need it. Need it. Need it."

Boss: "Maybe next quarter."

Me: "But Ann has a brand new computer and she can compile in just five minutes."

Boss: "Well, she had a really old one. She was due for a new one."

Me: "But I need one, too."

Boss: "I hear you."

The boss is reassuring me that he isn't ignoring my concerns. But he doesn't need to have me say any more, that would just be annoying.

I hear you, means I can hear the noises you are making

I am listening to you, means I am concentrating on the words you are saying to understand your point of view

"ya" is street argot.