A lot depends on what country your wife is from but, generally, if she wants to be able to continue working under her current permit (even after it expires) you should apply to sponsor her
via the inland process and include an
extension to her work permit WITH the PR application - and
both need to be received by the Case Processing Centre in Vegreville BEFORE her work permit expires. This is called "implied status" - it allows her to continue working under her original permit, even after it expires, until they finalize the first stage of assessment on her spousal application and issue her a new "open" work permit. This will take 9-10 months, so be sure to track the receipt of the spousal package and extension application to prove that it was received before her WP expires. Finalization can take another 3-8 months.
If you apply outland - yes, it will probably be faster (that depends on the embassy) - but she may not be able to get another work permit. She will need to
apply separately to extend her status, and it's safer in that case to apply to extend as a visitor. With proof of your legal marriage and the outland PR ap in process, she should be approved to stay in Canada as a visitor until her PR application is finalized. How long that will take depends on what embassy will be processing it.