Is this also a double-source-trolleybus ? How much of Mexico has infrastructure ready for that ? Or are they pure battery, it's not clear to me (trolleybuses are still used a lot in eastern europe, also in switzerland, but i wasn't aware that was so in Mexico ).
Those are purely battery-electric busses. This works pretty well for cities, as bus routes are usually short and most of the busses are needed during rush hour, so charging sessions in between are pretty easy to schedule. Its much harder with long distance routes, but if you build the charging infrastructure in strategic places, it should be doable.
Charging stations are usually located at the depot and some cities have charging stations at the last stations of a line. There are even wireless systems with pantographs either located on an arm touching down on the bus (panto-down) or going up from the bus to an electric rail (panto-up). For long distance routes, they will probably utilize somettjnf like this as well and charge at the stops for a few minutes.
I wish someone would make a large bus with lots of large doors. This bus is optimized for longer distance travel - it will take a long time to get everyone on the bus through that one door, thus meaning it must be stopped in one place for a while everytime a group gets on/off. The advantage is you can put a lot more seats on the bus.
Meanwhile most buses are used for short trips in areas where lots of people will be getting on and off. Thus they should optimize not for how many people can sit on the bus, but how fast you can get them on/off and thus to where they want to be.
Remember time your transit vehicle spends at a stop when you are not getting on/off is time robbed from you. People have places to be and the bus (except for a few 3 year olds is not one of them). One of the big issues people have with transit is how slow it is (and several others are a proxy for slow)
One of the pictures on the inside looks like there's platform level doors on the left. I could see it going into CDMX's existing or new BRT routes, where they already have articulated buses.