Considering the voltage difference between Europe and North America, will an E27 base bulb, in Europe, emit the same lumens as an E26 bulb in america?, Or will there be a different output because of lower American voltage?
Your question is whether the voltage will be a factor. Provided you are talking about different bulbs each built for the local voltage, it will not be a factor.
What makes any bulb emit light is power (in watts), not voltage or current.
Power = Voltage x Current, so for any change in voltage, there's a change in current that will make it the same power. Halve the voltage, double the current for the same power.
Lumen is an international unit so a lumen means the same thing everywhere.
No incandescent bulb that is designed to work on the American system will work on the European system. On the incandescent lamp, the resistance of the filament is altogether different. The higher voltage of the European system would incinerate the filament of the American bulb immediately. On the LED bulbs, those things have drivers that can handle a range of voltages. In this case, the lumen output would be the same. On CFL type bulbs, I am sure that those bulbs are designed to work on a specific voltage.