Yes. Two couples can do a private psychedelic session together in Amsterdam as a closed group of four, with no outside participants.
Choose a quiet, private, self-contained venue such as a full apartment or holiday home. Aim for one shared space for the opening and sharing, plus separate rooms or quiet corners so anyone can withdraw if needed. Avoid noise, thin walls, shared facilities, many stairs, or the risk of interruptions.
Align expectations beforehand: is the focus personal growth, connection within each couple, connection among all four, or simply a safe shared experience? Set clear boundaries about what you do and do not want to share, since each person still has an individual inner process.
Practical steps: each participant completes an individual intake to screen for medications, contraindications, past experience, and intentions. You can start with the intake here: complete the intake. Then coordinate date and the number of facilitators with your provider, and keep the following day free for rest and integration; a common rhythm is arrive day 1, session day 2, integrate day 3.
Hope that helps, and take your time to prepare well.