If your question relates to laboratories that are currently accredited to ISO 17025:2005, currently the certificates of accreditation to the 2005 version are valid; however accredited laboratories must transition before their certificate expires or by the latest, 1 June 2021. Accreditation bodies will arrange assessments against ISO17025:2017 before the deadline. That means that they need to be in the process of meeting ISO 17025:2017 requirements; thus making the old version of the Standard obsolete.
If you are busy implementing ISO 17025 and have not yet applied for accreditation, then no, ISO 17025:2005 is not applicable. The laboratory must implement to meet ISO 17025:2017 requirements.