So what you're suggesting, Jannik23, is that you pay for 200 hours at a reduced rate (around half the normal rate). However, you only put 100 of those in your logbook. The rest of the 1500 hours for your ATPL will come from your first job. Have I understood you correctly?
If that's what you're thinking, then yes, that's legal.
For what it's worth, the advantages/disadvantages of doing this (IMHO):
The downside (maybe?) is that the marketing of the school that offers this is (un-intentionally) misleading you into thinking that you're getting a very good price, when you're actually getting a fairly normal price. Nothing really wrong with this - it's not deliberate, because what they're advertising is perfectly clear to someone who grew up with the FAA system. Once a JAA license holder understands this, it isn't a problem at all.
The upside is that you get to spend 100 hours watching someone else fly, learning both good and bad points from another pilot. Which I would guess outweighs any negatives.
Incidentally, if you
do want to log your safety-pilot time,
LASORS (Section A, Appendix B) tells you how to do it. Entry N on the table is for a "Pilot acting as Safety Pilot". The operating capacity is to be "SNY", and you can "Enter time in 'Any other flying' or spare column and annotate 'SNY'." You obviously don't add it to your totals, though.
FFF
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