Large-ish cracks. Fillable, or replaster?

[DiyNoob21]

Hey all,

First time renovator here, looking for some advice on something i found when removing wallpaper. Images below, but essentially these cracks look pretty big and I'm wondering:
- Would it be possible to fill these with something like Tupret and then sand it back and paint over it?
- Or, are they too big and would likely still show so should be plastered over?
- OR, should I be worried that the house is going to collapse? (Hopefully not this one!)

Thanks in advance for any help or guidance.

 

[opps]

I would gun in some Toupret Fibacryl. Let it shrink back and then fill with a filler of your choice a day or two later.

 

[DiyNoob21]

Thanks for the advice! This sounds do-able even for me haha.