To configure sFlow v5 on Arista platform we recommend using following guide:
show run section sflow sflow sample 1024 sflow polling-interval 60 sflow destination 10.0.0.70 sflow source 10.0.0.10 sflow sample input subinterface sflow sample output subinterface sflow run
Then you need to enable sFlow v5 monitoring for each interface:
interface Port-Channel10 sflow enable
If you hardware support hardware sFlow v5 acceleration we recommend enabling it. In case of need for more information please check official guide