I think your daughter's reaction to so many changes is normal. She is now in a different environment (different country with it's different climate, appearances, food) a different house in a different bed, with different people. In a different time zone is a really big one.
I never feel really well for a couple of days once I get to Europe and I know what's going on. I chose to be there. Still I want to sleep on my home time, not this new time, and I want to be awake all night their time. It takes discipline and some "tricks" to get past jet lag.
My stomach also reacts to the different food and different water. Unless you took her food and water with you the food and water are different even tho it appears the same.
In addition to time difficulties in making the time change she is now in a home with a different routine. She's hearing voices that she doesn't know and hearing them in a language with it's different sounds and cadences than she's used to.
I agree. Hold her as much as she wants to be held. A front pack or sling may be helpful while you're there. Do
not insist that she interact with anyone else. Keep her schedule and diet as nearly the same as possible.
I'm not sure what you mean when you said she has a change in eating habits. Are the changes caused by the time difference, her not feeling well (could she have an upset stomach?) or because the food is different? I would try giving her soft comfort food and lots of liquids.
It sounds like you'll be there long enough for her to most likely be able to adjust. To make that adjustment she needs comfort from you and a schedule and diet as close to what she's used to as possible. She also needs for you to be confident that she will be alright. She will pick up on your anxiety and be more anxious herself.
I wonder if grandmother could be pushing to hold her granddaughter and be actively involved with her. If so try to get your mother to understand that she needs the security she can gain by being with you all of the time for a few days. It would be hard for me to not want and even insist on holding my granddaughter. I might even believe that my granddaughter will get over this faster if she gets to know me sooner. I don't think that's the case. She needs to feel secure before she will be able to leave your arms.
Your daughter will adjust if everyone can be patient, give her space, and let her do this in her own time. Neither her health, physical or mental, is in danger.
It doesn't hurt anyone, even a baby, to not eat much for a few days, as long as they get fluids. When she's ready, she'll eat. You've not said anything in your post to indicate the possibility of a problem with mental health. Now if you abandoned her, like not paying attention to her, and leaving her with your mother even thos she screams, she could suffer depression. The fact that you are asking these questions makes me think it's highly unlikely that you would do that. You are anxious about her well-being. You're going to take good care of her. Try to relax and just go with the flow. Provide for your daughter's needs just as you did at home. She's Ok. She just needs time to adjust without pressure and with much loving.
It's possible that her Daddy seems different to her. Perhaps he's anxious or tired or ???? With so many changes she's going to be more sensitive than usual.