It depends on how solid your claim of WA residency is. States will usually consider you a resident if you have a family domicile in that state, that you return to, even if you have a 2nd domicile where you work. See https://www.ftb.ca.gov/forms/2019/2019-1031-publication.pdf
CA generally requires the same filing status to be used for both federal and state returns unless one spouse is a full year nonresident AND that spouse does not have any CA source income. If the nonresident spouse is allocated CA-source income from the resident spouse due to community property law, the couple will NOT meet the exception for filing MFS for CA when MFJ is used for federal.
Reference: https://ttlc.intuit.com/community/state-taxes/discussion/re-married-couples-work-and-live-in-differe...
