Thank you for posting in the community your question about replacing object with specific objects. This is not a feature that is in Twinmotion currently and recommend you make a suggestion on the road-map for such feature: https://portal.productboard.com/7pu88c9kpmqtzt8hwg6arujh/tabs/4-under-consideration
However we do have a Replacement/Substitution Material feature and you can find more information about this here:
Currently what you can do is setup different views for the different types of trees species and export them as udatasmith files then import them in Twinmotion with the Keep Hierarchy Collapse method and use the Replace object function: https://youtu.be/R6rsATORnu4