I’m pretty sure you can, but it depends what performance you expect. My friend is even using MacBook Air and it’s enough for his simple projects (but to be honest its unusable for anything more complicated). Mobile GPUs are fussy, but R5 should be fine. If you consider buying one, wait till someone with similar configuration confirms it performs well. If you have one, why don’t you grab UE and try out yourself?
If the performance is bad you can try to lower your settings. Settings->Engine Scalability Settings as well as Material Quality Settings.
Thank you very much
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