I have a Lacie 4TB external spinning drive which is portable and does not require a separate power source. This is normally connected to my M1 Mac Mini via a USB 3 cable but I do have the option of using one of the Thunderbolt ports.
After buying this a few years ago I decided to partition the drive into three: One volume of which to be used as a Time Machine backup. A short while after doing this I seem to remember (please forgive me if I have this wrong), seeing one of your videos where you said something along the lines of that you did not recommend having Time Machine on a partitioned drive because it could cause problems in some way. I think you recommended having one drive used only for Time Machine.
I carried on using the drive as I had already set it up and I don’t think I’ve seen any problems. That is not to say that there are none, just that I haven’t come across any yet.
I am about to reorganise my Lacie drive into only two volumes now. One of these is to be used for Time Machine and I want to encrypt the other before I use it for media storage.
However, if I am about to make the same mistake twice, I would like to be able to rethink my plan.