bilby, it's easy to do research on exoplanet orbit periods. They range from a few hours to as much as a million years.
How in the world would we detect an exoplanet with a million year orbit? Just about every detection technique is based on observing something periodic about the system. And if you did manage to directly image an exoplanet you have no proof it is really is one and not something that simply lined up.
Cool Companions on Ultrawide Orbits - COCONUTS - "is a large-scale survey for wide-orbit planetary and substellar companions considered the first survey of this type of celestial bodies."
COCONUTS-2b and
Massive COCONUTS exoplanet discovery led by UH grad student | University of Hawaiʻi System News and
The Second Discovery from the COCONUTS Program: A Cold Wide-orbit Exoplanet around a Young Field M Dwarf at 10.9 pc - NASA/ADS
From the abstract,
The star is the M3 dwarf L 34-26
The planet is the T9 dwarf WISEPA J075108.79-763449.6
"Given their common proper motions and parallaxes, these two field objects constitute a physically bound pair with a projected separation of 594″ (6471au)."
No mention of radial velocity, however. Parallax: distance, proper motion: transverse angular velocity.
"The primary star COCONUTS-2A has strong stellar activity (Hα, X-ray, and ultraviolet emission) and is rapidly rotating (Prot = 2.83 days), from which we estimate an age of 150-800 Myr."
Then speculating on how the planet was formed, and ending with "Finally, at a distance of 10.9 pc, COCONUTS-2b is the nearest imaged exoplanet to Earth known to date."