I’ve never really looked for the data like that, so I played around a little. The MySolarEdge app as well as the solaredge.com web site are both reporting my production in MWh. It is currently reporting my lifetime production as 6.56MWh. I don’t know if it will get less precise as the lifetime number increases or not.
My Tesla app seems to still be reporting in kWh, but for me, at least, the Tesla app reports slightly lower production numbers than I get directly from the inverters. My Tesla app is reporting lifetime production of 6338kWh. I believe that in my case the discrepancy comes from the fact that the Tesla app is getting it’s numbers from the Neurio device inside my TEG, since I have a powerwall installation. In your case, with solar only the Tesla app will get it’s data directly from your inverters, so I would think that it would match what you see from SolarEdge. (Other than that missing 50kWh). I don’t know if the Tesla app will eventually switch to MWh with lower precision or not.
Someone who has had their system running longer than I have might be able to answer the question about whether the SolarEdge app or the Tesla app will lose precision as the numbers go up.