Editing the Transfer Update

Good day all, starting new save after a few years, just have some game set up questions, hoping someone can help:

I am using the latest summer transfer update.

Can I make further edits to this update in the pre-editor or something? When I check “import” and look at the Editor data folder nothing shows (I am guessing because its only FMF files?).

For example if I wanted the latest transfer update but wanted cancel all the loans for my team, how would I do this?

Also, can I use the realism update in conjunction with the the summer transfer update? Can I just drop in the FMF files that don't conflict?

Any help is much appreciated!

Cheers!