Which one of these would be correct?
"Articulations" are placed on the part of a tied note where they make sense (depending on whether they are relevant for the start or the end of the articulation). An accent would be placed on the first part, a staccato or tenuto mark or a fermata on the second. It would, however, be more customary to write a shorter note and a pause instead of using staccato marks since neither the "as short as possible" or "half the written note value" interpretation of a staccato mark are really comfortable to use on tied notes.
As a rule of thumb, try thinking about what will happen when the tie is broken across lines: where would you want to see the articulation in order to be able to play this properly?
Either is correct, depending on where you want the emphasis placed. Yes, I know an acoustic piano (or plucked string instrument) cannot achieve the exact effect, but all other instruments can.
And I suspect skilled pianists will use the suss pedal and gently restrike the key to approach a "hold and then emphasize" effect.
To go a bit further, suppose you were writing a "dot", indicating staccato. A dot over the lead note in the tie wouldn't make sense. (I would strongly recommend that any staccato note be written as a single flag rather than a tie. I'd find that easier to read)
Generally the first is correct.On piano, for example, that's the only way it would be played, even if the second was written. The second would be impossible to play on some instruments, although it may be exactly what's needed on, say, a trumpet part.
The first. Articulations are about how you START a note. (Except perhaps staccato dots, but then why would you lengthen a staccato note with a tie?)
I see what the second COULD mean, for some instruments, but I've never encountered it.