While LAs may make their own unlawful criteria (and pass these on to schools) the legal criteria that LAs must consider is:
whether the child or young person has or may have special educational needs (“SEN”); and
whether they may need special educational provision to be made through an EHC plan.
If the answer to both of these questions is yes, they must carry out an EHC needs assessment.
Two professionals have already indicated that your daughter would qualify, so I'd go ahead with the application. You already have lots of evidence. Everything you have written in these two posts plus any reports you have from the professionals that have already seen her.
She is "only a year behind". This isn't good enough.Every child is entitled to an education that allows them to reach their potential. If her needs were being met properly who knows what she is capable of?
All the things you mention are needs that are not being met and barriers to learning.
Being unable to focus could be down to sensory issues. If she is unable to focus she is not going to learn effectively. She may need to be in a calmer, quieter environment.
The fidgeting may also be down to sensory needs not being met.
She is behind with her learning. She may need a different teaching style/ provision put in place to help her learn more effectively.
She obviously needs a social skills programme to help her learn how to socialise, which would need intervention from a specialist.
Masking is very common among girls diagnosed with autism. But this leads to huge stress build up which results in the meltdowns and self harming. Support needs putting in place to reduce the anxieties.
Your DD needs to be fully assessed by all the professionals so all her needs and the provision to meet these needs are all clearly identified and documented in the EHCP.
Good luck. It will be a long process and you'll probably have a few battles along the way, but hopefully things will improve once the proper level of support is put in place.