BIG, really huge difference between these two circumstances:
I am a Canadian PR and plan to land in the new year.
Just to be clear - I got PR two years ago and did a soft landing around that time. . . . My partner and I have met since then.
I revisit this because it is a rather salient illustration of how important a single word can be. Here that word is "land." And the date of landing makes all the difference.
It also means your query is actually outside the scope of this part of the site (this part of the forum is about maintaining PR status). You are likely to obtain more current and more detailed information if you pose your questions about the sponsorship process in the part of this site which is specifically for topics about family class sponsorship (the most common of which, of course, is sponsoring a partner, whether married, common-law, or in a qualified conjugal relationship). Those topics are here:
https://www.canadavisa.com/canada-immigration-discussion-board/forums/family-class-sponsorship.5/
Examples of existing topics where proof of common-law relationship is the focus:
https://www.canadavisa.com/canada-immigration-discussion-board/threads/common-law-sponsorship-after-barely-1-year.648312/
https://www.canadavisa.com/canada-immigration-discussion-board/threads/proving-common-law-status.648052/
Those are just examples -- there are probably better discussions, more informative discussions about proving the common-law relationship, if you dig back through older topics in the family class sponsorship conference. And posting your query in your own topic there should generate more responsive replies.
Some Other Issues:
As a PR, to sponsor a partner you MUST be living in Canada, both at the time you apply and while the application is pending.
Residency Obligation: It also appears you may be
cutting-it-close in terms of complying with the PR Residency Obligation. If you landed two years ago and have not spent much time in Canada since, your window of opportunity to meet the RO is now dramatically shrinking. The longer you wait to come, the less flexibility you will have for the next two years after arriving. This site is rife with tales of woe told by PRs (many now FORMER PRs, having lost PR status) whose careful planning did not adequately accommodate contingencies, ranging from personal accidents to family emergencies, and not the least of which were employment/career demands . . . bottom-line is that many with plans to settle in Canada
just-in-time, so to say, that is
just-in-time to meet the RO, run into this or that circumstance which either delays their coming to Canada beyond what they planned, or compels them to travel abroad some after they come. A few years ago, for example, there was a volcanic eruption in Iceland resulting in widespread flight cancellations which led to many not being able to travel from Europe to North America for weeks. It is not uncommon to be involved in a motor vehicle crash resulting in injuries requiring one to stay put for weeks. Or, settling up and leaving a job sometimes takes longer than planned. For those
cutting-it-close, there is a risk of a delay.
REMEMBER: if at any time prior to the fifth year anniversary of the date of landing a PR has been outside Canada for more than 1096 days, as of that day the PR is inadmissible due to a breach of the PR RO, it becoming impossible as of that day to meet the RO.
For you, if there is a delay such that you fail to make it to Canada in time to avoid being outside Canada more than 1096 days since the day of landing, the risk is twofold.
There is the risk of being reported upon arrival at a PoE; this risk is fairly LOW initially but gets larger the more days you remain abroad.
The bigger risk involves making a sponsored PR application: if you are outside Canada more than 1096 days, since landing, as noted you will then NOT be in compliance with the RO, and it will take TWO years of presence for you to get back in compliance with the RO. And during that time you will NOT be eligible to sponsor a partner . . . here too there is some uncertainty as to how strictly IRCC might scrutinize your status, but if you are in breach of the RO (which you will be if you are outside Canada more than 1096 days since landing), the risk you take in making the sponsored partner application is not just the potential rejection of that application, but the risk of being reported for the breach and losing your own PR status. The latter may be fairly low if the extent of the breach is small, but here too that risk increases as the number of days abroad increase.
Inland versus Outland application: I do not have an example handy to link, but there are almost certainly some discussions in the family class conference about the pros and cons of so-called "outland" versus "inland" sponsorship applications. This is actually the main issue regarding which this forum (and a couple other similar forums) helped me considerably . . . but that was more than a decade ago. At that time there was a big, big difference in the processing timeline for "inland" versus "outland" applications, and a big difference in the risk of non-routine processing making the process even longer. Since I was already in Canada I initially thought we had to follow the "inland" process, but as
@Hurlabrick has pointed out, for an applicant living with his or her partner in Canada it is possible to make an application for either process, either inland or outland. Back when I went through the process the difference was big . . . my outland application resulted in a PR visa issued in barely four months versus an inland timeline, back then, which typically took a year just to get the OWP and two years to get the PR visa.
I am not familiar with how much difference it might make now. Again, see discussions in the family class sponsorship conference for more CURRENT information:
https://www.canadavisa.com/canada-immigration-discussion-board/forums/family-class-sponsorship.5/