So she's complete new to this.
If she's young and not too heavy, there's really no need to buy a full suspension.
A hardtail with branded basic parts can be found new form 2200 euro (Decathlon e-st900) to 2500 euro (Cube reaction 625)
The new bikes come with the beautiful square-round "allround"
Is is better in any way than the old spaceship marquardt.
Except it detects the pedalmagnet-hack.
But that's something for the derestrict-section.
They are plug- and- play interchangable, the mileage is stored in the motor.
This one doesn't look bad:
https://www.decathlon.be/nl/p/elektrische-mountainbike-e-expl-700-hardtail-29-flessengroen/_/R-p-334408
A bit more expensive, but it has a dropper and 4-pot brakes
I also thought about replacing the Kiox 300 with the Purion 200/400, but I ended up installing a Garmin Edge 1040 and removing the Kiox display.
Continuously charging the Garmin from the Bosch Kiox cable would be perfect !
The Edge power mount exists, I just need a version with 2 Bosch female...
No development needed there, and also no development possible.
Just leave the 250W-EU regulations class.
Those bikes exist for years, and just need a license plate and insurance.
I removed the Bosch display, and use a Garmin.
Garmin is capable of:
*showing the correct speed
*setup display pages
*connect to HRM
Pedal power is not possible unfortunately.
For Cadance/speed I installed sensors.
I know there are better ways but here's how I do it:
Drive till skipping on the 10t occurs, usually at 0.7 to 1.0 chain wear.
This time: Replace Chain +10t+12t
Next time: Replace chain, 4 smallest cogs, chainring.
I never had to replace the rest of the cassette.