Thanks. All of my shoes were purchased in last 5 yrs with batch numbers above 100.000, so that wouldn't necessarily explain what I am experiencing. I do think it could be related to differences between the lasts, as it was suggested that for an MTO they could have those made on the same last of a shoe that fits me well. Upon further inquiry, it seems the factory can't tell which last down to that level of detail.Do any of the shoes have a batch number sub 100.000? If so, that could explain some of what you have been experiencing. Somewhere around the 100.000 mark, E.G. shifted away from the usage of wooden lasts over to resin lasts, because the wooden lasts were prone to shrinkage over time due to wood being a natural product and it presumably also being exposed to moisture during the shoe making process. This shrinkage of the lasts lead to some inconsistencies in sizing. Resin lasts however should be immune to shrinkage, so the thought was that from the introduction of the resin lasts on, sizing should pretty much have remained consistent, especially within the same last and size.
If I recall correctly, the switch from wood to resin lasts took place around 2015.
At the time many E.G. wearers claimed that while remaining on the same last and size, shoes that were made on the resin lasts, felt about half a size larger compared to ones that were made on the wooden lasts. Some actually were of the opinion that sizing down half a size was merited. I however, was able to remain on the same size as always and did find the new lasts to deliver overall a more consistent sizing compared to what I was used to on wood and the shoes were just a tad more roomy than what I was used to.