do origin players see my origin name on apex when i play on steam

You log in to the game with an EA Account anyway, so in both Steam and ex-Origin version of Apex Legends the game uses your EA Account nickname during matches.

Do origin players see my origin name on apex when i play on steam? - NO. They see your Steam Display Name. 

If you(on steam) see your friends(on origin) is Origin Name.

If you(on origin) see your friends(on steam) is Steam Display name. 

What good about steam is, Your IGN is Steam Display Name. Not your steam login name.

What Bad about Origin is, Your IGN is your Login Origin name.

That's why there's an option on Apex where you can hide your display name 'Streamer Mode'(I think).