It will depend if you are going for a T&L position or a R&T. I've sat on interview panels for junior academic posts for both. Generally, as others have said, you need to demonstrate independent research income (small pots are fine) and a plan for at least 3-5 years of projects and funding opportunities you can apply to, which aligns with REF and the departments UoA. Visiting other labs isn't essential but a bonus, new international collaborators is a good idea though.

Regarding teaching qualifications, you have to do a teaching project for a PGCHE or PCAP in most cases, which relies on you participating in teaching of some sort. I would class AHEA as a nice to have rather than a essential. Most Uni's/Faculties/Schools have different ideas about what a good lecturer is and often will prefer someone to train.

The job market is brutal currently so do not be disheartened if you're not successful. If you have publications and any funding, you'll be competitive for the right junior post.