Wall connections, corners, joint formation Fermacell

Are there recommendations for edge protection (profiles) specifically for window reveals to make 90° external corners? There are different systems from manufacturers: paper-wrapped metal, self-adhesive plastic strips activated with water (Aquabead), plastic strips for embedding (Levelline), aluminum rails, etc. For some, special tools are needed to apply the filler directly onto the rail.

What do you use or what would you recommend? Cost-effectiveness takes precedence over time-saving.

Thank you

Questions again:

If the drywall walls and ceiling are plastered with fine plaster, does a separation layer with Trennfix have to be applied between the wall and ceiling? And how do you get the Trennfix neatly cut, since the fine plaster has a certain texture, making it difficult to cut cleanly?