Peer review is not too bad a way. Be sure that reviewers are neutral, that they are experts and that they do their job.

Refereee should be chosen really experts and neutral

Questions similar to yours had been posted also here in RG. Please see the links to find some answers.

https://www.researchgate.net/post/What_is_the_best_plagiarism_software_that_can_be_used_to_detect_plagiarism_in_Master_Sci_thesis_in_various_languages

https://www.researchgate.net/post/Is_there_any_free_open_source_and_good_software_for_originality_checking_like_turnitin_CrossCheck_etc?_tpcectx=topic_detail&_trid=qS2YzAFrjmB5d5YSx3cvnj8d_8

https://www.researchgate.net/post/Is_there_any_open_source_plagiarism_checking_tools_as_efficient_as_turnitin?_tpcectx=topic_detail&_trid=QMeiyWKiczP9mEUZZuCMxbAd_10

https://www.researchgate.net/post/Is_there_any_free_plagiarism_detection_software?_tpcectx=topic_detail&_trid=tkg5YnGEewr1T6Z0Z5yHEKdz_11

What is the best way to check originality of research paper ?

You can explore some free plagiarism software as shared below:

https://www.researchgate.net/post/Is_there_any_open_source_plagiarism_checking_tools_as_efficient_as_turnitin

https://www.researchgate.net/post/I_need_to_check_my_thesis_with_a_plagiarism_tool_like_Grammarly_or_Turnitin

https://www.grammarly.com/plagiarism?q=plagiarism&utm_source=google&utm_medium=cpc&utm_campaign=Search&utm_content=56705349966&utm_term=detect%20plagiarism&matchtype=b&placement=&network=g&gclid=Cj0KEQjw5ti3BRD89aDFnb3SxPcBEiQAssnp0jnAJxWV8gvlimrEyjxsseLOcvtb9prIClBlyD7Y1Z8aApmK8P8HAQ

http://www.plagius.com/s/en/home

https://www.plagramme.com/?gclid=Cj0KEQjw5ti3BRD89aDFnb3SxPcBEiQAssnp0sCiIfrPgob6dxmqxxstHqRM_ULNSa0pJvCmColUH3oaAojR8P8HAQ

https://www.researchgate.net/post/Can_someone_advise_how_to_configure_Viper_in_Http_connections

Thanks to all of you for excellent response.