In the first of these two articles showing paintings of the first act of this play, the fairies attending Titania had just sung her to sleep, allowing Oberon to drop the herbal juice onto her eyelids, which would make her fall in love with the first creature she saw when she woke up.

Richard Dadd’s Titania Sleeping from about 1841 is another elaborate example of faery painting with its intricately detailed human-like creatures. The naked queen has just fallen asleep at the mouth of a grotto. Framing that scene are toadstools, morning glory flowers, and an arch of bats.

Robert Huskisson’s The Midsummer Night’s Fairies (1847) shows a simpler version of a similar scene.

Gustave Doré’s A Midsummer Night’s Dream from about 1870 is even grander, with a full moon shining through the trees of the wood.

John Simmons’ undated watercolour of Titania Sleeping in the Moonlight Protected by her Fairies is another variation, and one of a series of paintings he made of this play.

Simmons’ watercolour of Hermia and Lysander from 1870 shows the couple in a thoroughly enchanted wood, with an owl, a peacock feather, foxgloves, cobwebs, and sundry tiny fairies.
Lysander and Hermia finally meet, but decide to spend the night in the woods and settle down to sleep. Robin Goodfellow, sent by Oberon to apply herbal juice to the eyelids of Demetrius, mistakes the sleeping Lysander for his target.
Helena has fled from Demetrius, and inadvertently wakes Lysander, who immediately falls in love with her; when she takes flight, he pursues her, abandoning Hermia to awaken alone.
Elsewhere in the woods, the cast of the play are starting rehearsals, rapidly rewriting its script to take out the deaths of the two lovers and cast moonshine and the crack through which the couple speak with one another. Robin Goodfellow transforms Bottom’s head into that of an ass, which drives the rest of the cast away. Titania then wakes up, sees Bottom and instantly falls in love with him, providing him with fairy attendants before taking him off to her bower.

Henry Fuseli’s painting of Titania, Bottom and the Fairies from 1793-94 shows the queen with her arms around the unfortunate Bottom, while attendant fairies serenade the couple.

Painted by George Cruikshank in about 1845, shortly after the restoration of Shakespeare’s original play, A Midsummer Night’s Dream, Bottom the Weaver and Titania is an unusual tondo showing a very large Bottom relative to its tiny Titania, under a crescent rather than full moon.

In the middle of the nineteenth century, between 1848-51, the leading railway engineer in Britain, Isambard Kingdom Brunel, who built the Great Western Railway, commissioned one of Queen Victoria’s favourite painters Edwin Landseer to paint Scene from A Midsummer Night’s Dream. Titania and Bottom. This was hung in Brunel’s dining room alongside other paintings of Shakespearean themes.

Paul Gervais’ more modern take, in his Madness of Titania from 1897, adheres faithfully to Shakespeare’s classical setting. This was exhibited at the Salon in 1897, where it was purchased.
While Oberon is delighted at Robin Goodfellow’s success with the queen, when his mistake with Lysander becomes clear, the king decides correction is required. When Demetrius is asleep, the puck puts herbal juice on his eyelids and fetches Helena, who is still being pursued by the besotted Lysander. Demetrius then awakes and he too falls in love with Helena. Hermia is the next to arrive, but her longstanding friend Helena accuses her of breaking their friendship. Demetrius and Lysander go off to fight, and have to be kept apart by the puck. Acting under Oberon’s order, Robin then applies herbal juice to Lysander’s eyelids, accompanied by a magic spell to restore his love for Hermia, and resolve the conflicts between the two couples.

John Simmons’ watercolour of a Scene from A Midsummer Night’s Dream from 1873 is a composite based on this late scene in the play. Hermia and Helena are both asleep as the reunited Titania and Oberon glide through the sky behind them, and sundry fairies decorate the view. Also in the air, presumably bearing magic herbal juice, is Robin the puck, to the left of centre.

Henry Fuseli’s liberal fantasy of Titania and Bottom from about 1790 is loosely based on the opening of Act 4 Scene 1 with Titania’s words:
Come, sit thee down upon this flowery bed,
While I thy amiable cheeks do coy,
And stick musk-roses in thy sleek smooth head,
And kiss thy fair large ears, my gentle joy.
Titania (left of centre) calls on her fairies to attend to Bottom, who wears the ass’s head to the right of her. Peaseblossom scratches Bottom’s head, with Mustardseed on his hand, and Cobweb kills a bee to bring its honey to him. Fuseli has borrowed liberally from other sources: Titania’s pose is from Leonardo da Vinci’s Leda (c 1506), the elves at the right from a Botticelli illustration for Dante’s Paradiso (c 1469), and the girl with butterfly wings on her head in the left foreground is based on some of Reynolds’ child portraits.
Titania and Bottom arrive and settle to sleep once their fairy attendants have left them. Oberon has at last succeeded in getting the changeling from her, so undoes the spell binding her in love to Bottom. She wakes, Bottom’s human head is restored, and the king and queen dance together and leave with the puck.

Thomas Stothard’s Oberon and Titania from 1806 refers to this reconciliation.
Theseus, his bride Hippolyta, and Egeus arrive to find the four lovers also restored to their former relationships. The Duke decrees that Hermia can marry Lysander, and Helen can marry Demetrius, when he and Hippolyta are wed. Bottom also wakes up and dismisses the events of the night as a dream, before going to rejoin the other players.
To pass the time before his wedding, the Duke invites the players to perform Pyramus and Thisbe, which takes place as a farcical play within the play. After a travesty of the prologue, the actors explain their roles, such as Smout the tinker playing the wall through which the two lovers speak. Once the couple are both dead, that play concludes with a bergamask dance (from Bergamo, Italy).
With the three couples away in bed, Robin Goodfellow arrives and sweeps with a broom, ready for Oberon and Titania to bless the house, the three couples and their future children.

William Blake’s Oberon, Titania and Puck with Fairies Dancing (c 1785) is one of his large early watercolours, showing Oberon and Titania at the left, with the puck next to them and facing the viewer. In the words spoken by Titania to her fairy train:
Hand in hand, with fairy grace,
Will we sing, and bless this place.
The puck closes the play with the suggestion that the audience dismisses it as a dream, or applauds.
References
Wikipedia on Shakespeare’s play.
Full text at Project Gutenberg
Michael Dobson and Stanley Wells (eds) (2015) The Oxford Companion to Shakespeare, 2nd edn, Oxford UP. ISBN 978 0 19 870873 5.