Is UPlay required for Offline Single Player in the Assassin's Creed Franchise?

Question

I've been thinking about getting the Assassin's Creed series for PC when they next come on sale. last time however what stopped me was that aside from the first one Steam has the following notice on all of them

Requires 3rd-Party Account: Ubisoft Account (Supports Linking to Steam Account)

This is a deal breaker for me as my setup for Steam on my PC is generally offline play always (downloads are on a laptop and i've never needed to verify my account on my PC) and a "requirement" for a third party account to me makes it sound as if i need to go online to create and log into a UPlay account to play single player. also requiring to go online to log in to play a single player game to me sounds very much like DRM and i'm anti-DRM

It is my understanding however that Halo on Steam has a similar notice but for XBox Live and that this is just for multiplayer, meaning that for someone who would play it for single player only offline, the third party account wouldn't be needed. and when me and my father played Assassin's Creed on the XBox Consoles neither one of us needed to make a Uplay account or be online.

I am aware of a a question from 9 years ago talking about DRM in Assassin's Creed 2 and i would consider needing to log in to play a single player game offline as DRM, but none of the pages actually say there is DRM (not that it's a guarantee. Denuvo is in Code Vein's 3rd-party EULA but not mentioned on the store page)

So i am wonder if any game on the Assassin's Creed Franchise requires UPlay to play offline single player

Answer 1

As far as I know, even for offline play you need to run Uplay (seemingly owning a game on Steam isn't enough grounds for Ubisoft to assume you probably got it legally), so you will also need an account.
Steam can then be put in offline mode, too.

According to Ubisoft's FAQ:

As long as you have already logged in successfully once, the client is designed to switch automatically to offline mode if you do not have an active Internet connection or cannot connect to the game servers.
Also, if you wish to force the client to start directly in offline mode, you can tick the Always start Uplay in offline mode box in the client Settings, or via the main menu by selecting Go offline.

While in Offline mode, most features will be unavailable, but you can start your game from the Games tab as usual. Almost all games in our current catalogue can be played offline after they have been activated, providing they do not have any always online requirements, and your solo campaign will resume from the latest local save.

An example: you can play Assassin's Creed Origins completely offline for up to 30 days, after which you'll have to sign in to Uplay again.
Same goes for Odyssey.
I have just tested playing Assassin's Creed II through offline Steam through offline Uplay, and that worked fine.

Be sure to check for each game it's actually saving your progress while offline.