Hi,sorry for the late reply but I've been a little remiss on my used-to-be-daily reddit browsing haha. It is indeed a broad question,perhaps one too vast for a single reddit answer but I'll just boil it down to the general idea and will be happy to answer any other,more specific queries you might have. The relationship between Korea and Japan was friendly at times,mostly disparaging and occasionally hostile. Hopefully,you'll see this reply !

TLDR : Yeah they traded right before Meiji but it's cuz money dosen't stink and they each thought they themselves were the best and the other an inferior.

Korean contact with Japan is both ancient and difficult to summarize,spanning 2 millennia and varies in accordance to the period,with speculation that the original "Japanese" migrated over to Japan via the Korean peninsula. Korea was also instrumental in transmitting Buddhism and the knowledge of China,the knowledge of bronze,the trade of mirrors and general political influence (via marriage) was common. As Japan maintained direct contact with Tang China in the 600-700s, the nature of these relations changed as well,namely that they viewed each other as inferiors to Tang China. In the case of early Japan,the severing of relations with Silla in 799 while the Silla viewed them as barbarians who similarly,did not deserve any of the missions Silla often sent to neighboring kingdoms. During the Goryeo period (the early 9th–11th centuries),this pattern was,in general,the norm; Diplomatic silence officially and private merchant trade continuing unofficially.

Matters weren't helped in the later centuries as Japanese raiders and pirates,known as Wokou in Mandarin and Waegu in Korean were a constant threat to the region, with Joseon Korea having recorded a number of extensive campaigns against the Japanese pirates.Trade eventually coalesced into an official clan mandating trade with the then Joseon Korea (1392-1910),the Sō. The Sō were jito (stewards) of Tsushima,ruling the island in the name of the actual shugo,the Shōni and gained their wealth not from taxation of obscure and sparsely-populated Tsushima (though that certainly played a role in their wealth) but from trade with Korea. Indeed, for the majority of Kamakura-Meiji Japan,the Sō clan was responsible for trade with all of Korea on behalf of Japan and that was the nature of the relationship with Korea and Japan until 1592: trade. The Koreans bought Japanese silver with Chinese silk,jade and bronze coins while having a few marriages here and there. The Sō,and by extension the Japanese, enjoyed these goods which they could not directly enjoy from China due to the Ming's aversion to all Japanese trade via the Haijin ban,banning all trade with Japan due to both perceived and real pirate raids conducted by the Japanese. Joseon embassies to Japan and vice versa were common from 1392-1443,primarily due to the efforts of the 3rd Muromachi shogun, Ashikaga Yoshimitsu, who opened up Japan to foreign trade and received emissaries from both the newly minted Ming China and Joseon Korea,before lapsing into a quiet whimper after 50 years. Informal trade with the Sō however was a constant and steady thing,continuing up till the Imjin War. This awkward relationship came to a grinding halt in 1592,when Toyotomi Hideyoshi,kampaku of Japan,launched an invasion of Korea as a prelude to conquer all of East Asia (China as well),known to history as the Imjin War,which lasted 6 years and was a cause of great suffering to the Korean people who bore the brunt of the invasion.

Post-Imjin is where it gets really interesting,however,cuz the natural instinct is to assume diplomatic aversion due to the immense amount of bad blood between the two nations. The truth,however,was the near exact opposite.Edo Japan,under the newly minted Tokugawa Shoguns were desperate to maintain peace as a failed war was the very thing that had dethroned the previous ruler of Japan,Hideyoshi and recognized Korea as the single most important nation to have relations with in the burgeoning Edo period,culminating in an invitation for a Korean envoy and an agreement known as the Treaty of Giyu ( 기유약조), which re-opened trade with the Sō clan of Tsushima and allowed for the first time in about 150 years,the restoration of diplomatic missions to Japan,roughly every 7 years after 1617-43 (Tongsinsa),which then slowly dulled down to congratulations during the enthronement of a new shogun or during a specific request by the Japanese authorities that the Koreans send one to learn of the developments in the Korean peninsula. The Koreans often re-invited Japanese delegates to come to Korea as part of diplomatic protocol after a Japanese invitation but,to quote the Japanese Exclusion Edict of 1636:"No Japanese ship ... nor any native of Japan, shall presume to go out of the country; whoever acts contrary to this, shall die, and the ship with the crew and goods aboard shall be sequestered until further orders. All persons who return from abroad shall be put to death (hence their one-sided nature) "

This Tongsinsa bilateral exchange was often a grand event,involving Korean dignitaries that numbered in the hundreds and often involved re-affirmation of trade,cultural exchanges (The Koreans,in particular,were interested in Japanese swordsmanship in the early missions) while disseminating Confucian classics and popular Chinese commodities like silk and jade and porcelain that the Japanese were unable to obtain due to the tumultuous times for Ming China and the early Qing's disinterest in Japan in general. As a fun fact,the sweet potato is credited to one of these missions,specifically the 1764 one,after the sweet potato was introduced as a banquet dish by the Japanese cooks,which was apparently a big party. The renowned Edo poet, Fukuda Chiyo-ni,one of the great female Haiku poets,is known to have performed in this banquet and personally presented Japan's gift to Korea in return : 21 hand crafted pieces of art based on her most famous haiku poems. These missions were the general norm of diplomatic affairs for most of Edo Japan till the forced opening of Korea's borders by Meiji Japan in 1876.