A7 III vs X-T4

[himeshlem79]

Hi guys, I was wondering if someone can give me some advice on buying a new camera. I currently have a a5000, with an 18-55mm lens, 50mm prime lens and a samyang 12mm manual lens. Im not massively into photography (I'm getting there) and I feel my a5000 is just a little lacklustre for what I want - I usually take photos of landscape and animals (from dogs to insects, particularly when they are moving). I feel the a5000 isn't great at autofocusing, especially on moving insects, so I'm looking for something that will be better for this.
I am also planning to do a phd in the next few years, where I may need to take landscape shots.
Which would be better, the X-T4 or the A7 III?
I do like the design of the X-T4, however I know I would need to buy whole new lenses. I like the design of the A7III too, however I know the APS-C lens that I currently have might not work great on the full frame.
Is there a particular system to go for for lenses (fuji vs sony)? Alternatively, if there are any other cameras you can recommend, I'm open to them. I have a budget of about £1500, but I don't mind spending more if the camera will likely be future proof for the next few years
Thanks

 

[Ysarex]

DPReview is a good site to use for comparison shopping. From reading your question the criteria that surfaces as most critical is auto focus on moving subjects: Best cameras for sports and action in 2021