B1 type training as per Part 66 requirements can only be delivered by a Part 147-approved MTO with an approved course for the aircraft concerned.
As such the classroom hours for the "Theory" element are prescribed by the MTOE, as are the frequency and nature of interim and final tests; and they must comply with Part 66 requirements, of course.
Europe's tectonic plates will have to shift a long way before every Member State will agree to doing all that on line. It's as much a question of attitude as of the practicability of achieving robust training and testing online.
About 5 years ago, at a Workshop on developments in engineer training, a gentleman from UK CAA gave an update of their progress towards on-line examinations for Basic Training Modules. He announced proudly that he and his team had been working on this for about 6 years, and that they were confident of arriving at a solution within another 3 - 5 years. There were a number of people in the room from different organisations, who could have told him in 30 minutes how it could be done with 100% robust reliability, but we knew it would be futile, so we just had a little laugh and moved on.
I only mention that to illustrate the obstacles that will have to be overcome. My own view is that good, well-prepared material can be used on-line to teach theory, with robust, "proctored" (ie properly supervised) testing. However, that would need to be accompanied by longer, better planned and executed Practical training and OJT than most MTO's get away with at present. After all, what counts is practical knowledge and experience, supported by good theoretical knowledge; currently we seem to have this the wrong way round.