The two boggarts seem like different creatures, both closely related to brownies. Maybe they could be converted as a boggart (#239 version) and a "fallen" boggart (#54 version)?
Boggart
From Dragon #54, created by Roger E. Moore
(Note: The text for doesn't seem correctly typeset in the PDF version from the Dragon Magazine archive. Several words seem to be missing. I don't have a print copy of #54 to check, alas.)
FREQUENCY: Very rare
NUMBER APPEARING: 1
ARMOR CLASS: 3
MOVE: 12"
HIT DICE: 1⁄2
% IN LAIR: 10%
TREASURE TYPE: J, K, L on individual
NO. OF ATTACKS: 1
DAMAGE/ATTACK: 7-3
SPECIAL ATTACKS: Spells
SPECIAL DEFENSES: Never surprised; save as 9th-level cleric
MAGIC RESISTANCE: As above
INTELLIGENCE: Average to low
ALIGNMENT: See below
SIZE: S (1 1/2' tall)
PSIONIC ABILITY: Nil
Attack/Defense Modes: Nil
When, for any reason, an alignment change brownie, the formerly lawful good creature is transformed into a boggart, or "boggie." Boggarts are solitary little creatures, with extraordinary senses and dexterity (just as the they are not surprised and have 18 dexterity with a capabilities) and may also become effectively invisible in natural terrain because of their skills at hiding.
Boggarts do not possess the same spell powers as brownies do; three times a day a boggart may shapechange, hideous form that will cause a save vs. fear, at +2, for it. In their normal shape, boggarts are small, hairy folk, something like a miniature bugbear. They have dark tan brown fur, with light nut-brown skin on their hands, feet (soles only), and faces.
Boggarts enjoy creating mischief, but can be and aren't very wise at all. A randomly encountered boggart can be chaotic neutral (60%), chaotic evil (20%), true or neutral evil (5%). Evil ones may be found as servants of assassins. Neutral (with respect to good and evil) boggarts can sometimes be found living with families in cottages, more or less as pets, occasionally harassing the occupants with (usually) harmless practical jokes.
Boggarts speak only their alignment tongue (a corrupted form of the brownie language, understandable by 50% of all brownies) and common. The change from brownie to boggart is reversible only by a Wish spell. If a brownie was a familiar to a lawful good or lawful neutral magic-user before the change, he will become hard to manage (at best) in boggart form and will run away.
Boggart
From Dragon #239, created by Brian Corvello
CLIMATE/TERRAIN: Temperate/Urban
FREQUENCY: Rare
ORGANIZATION: Solitary
ACTIVITY CYCLE: Night
DIET: Omnivorous
INTELLIGENCE: Very (11-12)
TREASURE: F
ALIGNMENT: Lawful Good
NO. APPEARING: 1
ARMOR CLASS: 2
MOVEMENT: 12
HIT DICE: 1
THAC0: 20
NO. OF ATTACKS: 0
DAMAGE/ATTACK: n/a
SPECIAL ATTACKS: Spells
SPECIAL DEFENSES: Invisibility
MAGIC RESISTANCE: 10%
SIZE: T (1' tall)
MORALE: Steady (11-12)
XP VALUE: 270
Boggarts are tiny, helpful cousins to brownies who live in extremely old buildings. They much prefer inhabited homes to abandoned structures.
Boggarts are invisible to all but the most innocent of humans. These are usually children, but occasionally a very good paladin or lawful good priest can see them. Those who have viewed boggarts describe them as funny little men with big noses and colorful clothes. Boggarts speak the common tongue as well as the languages of elves and brownies.
Combat: Boggarts shun fighting, and they hate evil creatures. When one enters their home, they use their spell abilities to torment the creature in hopes of driving it away. Boggart pranks may include making an offending creature’s hair grow, turning it green, or making it trip over the furniture.
Boggarts have several spell-like powers to help them with their jokes. At will they can use faerie fire, ventriloquism, dimension door, audible glamer, cantrip, and telekinesis (50 lb..). As noted, they are invisible to most creatures, and only detection spells can reveal their presence.
Anyone who is cowardly enough actually to kill a boggart becomes the recipient of a debilitating curse of the DM's design. This may be lifted only by a remove curse spell by a caster of no less than 12th level.
Boggarts have a particular weakness: they are frightened by loud noises, which cause them to make a Morale check or flee.
Those who can communicate with boggarts find them a great source of information. Assume that any boggart is 50% likely to know any fact about the area in which they live, 80% if that knowledge involves other fairies.
Habitat/Society: Boggarts are helpful creatures who live in houses belonging to very good people, helping out with chores and such after the family goes to bed. They also have been known to play with young children, but they vanish when a disbelieving adult is near.
Boggarts never accept payment for their help, though if someone leaves out small scraps of food for them, they gladly gobble it up.
Boggarts are usually solitary, though every month at the night of the full moon, dozens--or even hundreds--of boggarts gather in one area for a big festival. Very few mortals have seen these merry occurrences, and those who have tell that strange secrets can be gleaned from them.
Ecology: Boggarts are primarily vegetarians, though they may eat sausages and smoked meats at their festivals.
Boggarts don't hoard wealth, but some may have a small amount of treasure collected over the years. A boggart may be convinced to give up his treasure if he's sure it will go to a worthy cause.
