For the last 12 years or so I've worked extensively in all arrangements and here's what you need to know.
Outsource: Generally this conflates 2 actions. One is paying for a cheaper labor market. The second is paying for less skilled people. Most of the projected cost savings come from the latter. Most of those projected cost savings don't appear. I remember folks hiring $10/hr DBAs in India and the result was about what you'd expect. India is full of great DBAs and they ain't charging $10/hr or at least they haven't for a long time. It is the case that you can access a cheaper labor pool. Most people do this and then negate that savings by not creating a remote-first culture and introducing massive language and time zone barriers and friction due to multiple companies interacting.
Offshoring: The key difference here is that these are part of your company. In the US it's totally possible to set up an office in central/south america in-timezone and staff it with amazing people and save some money. Well, except for most of those folks who are willing to relocate will eventually accept offers with FANG companies either locally or relocate. So it's a nice scheme while it works. (Hi to all my tico friends now at Google and Amazon)
Remote: this is what most people confuse for the above two things. Remote is about doing 2 things.
1) Expanding your hiring pool beyond a 30 minute commute from your office (turns out that the other 99.99% of the world's population also has some great folks).
2) Making your company culture remote-first. But that's synonymous with writing things down and documenting things.
Sure interpersonal relationships can be trickier to bootstrap and that's a real cost. But see #1, nobody talks about that cost.
The final thing to keep in mind is that for most big companies, there's no way to avoid the remote cost. As soon as you open up an office in another location you're a remote company. Hell, as many people can attest as soon as you ask people to attend meetings on another floor or an adjacent building you find out you're a remote company.