Can Unchained Rogues use all Rogue Talents available to Standard Rogues? If not is it ok to multiclass an Unchained Rogue with a Standard Rogue?
Some rogue talents are available to unch. rogues
The following rogue talents from the core rogue class can be used with the unchained rogue without modification: assault leader, black market connections, canny observer, cunning trigger, deft palm, distracting attack*, fast getaway, firearm training, getaway artist, grit, iron guts, ninja trick, positioning attack, quick disguise, quick trapsmith, rope master, strong impression, strong stroke, survivalist, swift poison, underhanded, wall scramble.
Furthermore, all talents available to unchained rogue are available on this page of the official reference website Archives of Nethys.