Is there something sweet like fresh fruit or dried fruit which she likes, a kind of "go to" which you know she'd want? When mine had a phase of being a bit off his food I found if I put a few sultanas on his plate he'd go to those first and it would really get his appetite started, then he'd eat well but without the sultanas to get him going he'd seem to just not be hungry.
I would say at this age she is capable of bringing a spoon or fork to her mouth even if she can't stab or scoop the food herself, it's a skill like any other which takes practise but if you encourage her or do hand over hand a few times this might help to reduce the frustration as she may feel more like she is feeding herself but getting the help she needs.
Mine liked to have proper cutlery, not baby cutlery. Perhaps that would help? I got the kids stainless steel set which looks just like adult cutlery but is smaller and lighter for little hands.
At 1yo I saw a significant drop in appetite with mine (enough to be a bit concerned) and then discovered that many 1yos have this. It's like they just don't need the same calories any more. Then the appetite picked up again around the time he started walking more and climbing etc. Perhaps this is having an impact too? A natural drop in appetite?
Another phase I noticed was one where my DS no longer trusted the food on his plate. It was around a developmental leap and whilst other aspects of his understanding of the world were changing it brought with it a distrust of food. Just like a court jester I 'checked' every pile of food for His Majesty (
) and said "mmm, no poison there, that's good, let me check this, mmm, yes that one is good". Honestly once I had checked he tucked right in! Although it went on several weeks it was only a phase and he got over it. Might be worth a thought?