YES, you can transfer your booking to your own TA.
We booked our 1/2023 trip on board. It was transferred to our TA immediately. Within hours, TA and I had the third-party insurance taken care of (so that we could meet the 14 day deadline for existing conditions). I'd rather book with a 3rd party company because if I have to cancel, I want my cash back, not a voucher for a future cruise.
If you know which TA you are going to use, make sure that it is transferred immediately.
Whether the consultant knows about them or not, they can be added after the fact (one voucher per guest per cruise for a net saving of $100 per person; in other words, stop worrying about because it isn't worth the bother). If the question is if you can book a cruise and then buy the vouchers to apply to that cruise, I don't know the answer.