I can confirm that there were at least some West-Slavic (Wendish-Abotrites) settlements in now southern Sweden and eastern Denmark, especially in some cties like Lund, Roskilde and Sigtuna.

While it has been relatively well-known among the researchers that the 'Baltic' (aka Slavic-Wendish) ceramic wares spread extensively in these western Baltic region up to the end of the 12th century, some place (quarter) names like Vindeby ('the farmstead of the Wends') or Vendebode, as a city quarter in Roskilde, Sealand (Denmark), suggest that they got their name from flowing new Slavic settlers like craftsmen and merchant in the emerging town landscape in medieval western Baltic (Andersen in Harck & Lübke hrsg. 2001: 132f.; Cinchio 2003: 91). Some of 'Baltic wares' could also be made domestically by such incomers in the cities.

On the other hand, I haven't heard any corresponding archaeological evidence either from Iceland or from the coastal towns in the British Isles to justify the hypothetical Slavic-Wendish settlements. The archaeology in late medieval and early modern Iceland, especially its connection to the outer world still has much room to be explored (Cf. Mehler 2009), but I suppose the new settlers during that period should rather be classified as the 'Germans (of Hanseatic cities' rather than the Wends. It might be also worth noting that medieval Iceland didn't have any coastal fishing settlements (some might have been of foreign, immigrant fishermen) at least until the end of the 13th century. In was not until the beginning of the 15th century that any non-Norse (Scandinavian) newcomers got into trouble with other Icelanders, and it was the English, not the German, in the first half of the 15th century.

AFAIK Mats Roslund (Historical Archaologist, Lund Univ.) is the foremost expert on the topic asked in OP, but he has not written many articles in English. At least I attach a link to one of his article in Sweden, but I'll be sorry if OP cannot understand Swedish.

References:

• Cinthio, Maria. De första stadsborna: Medeltida gravar och människor i Lund. Stockholm: Brutus Östlings, 2003.
• Harck, Ole & Christian Lübke (hrsg.). Zwischen Reric und Bornhöved: Die Beziehungen zwischen den Dänen und ihren slawischen Nachbarn vom 9. bit ins 13. Jahrhundert: Beiträge einer internationalen Konferenz Leipzig 4. -6. Dezember 1997. Stuttgart: Franz Steiner, 2001.
• Mehler, Natascha. 'The Perception and Interpretation of Hanseatic Material Culture in the North Atlantic: Problems and Suggestions', Journal of the North Atlantic, 2(sp1), 89-108, (1 January 2009). https://doi.org/10.3721/037.002.s109
• Roslund, Mats. Guests in the House: Cultural Transmission between Slavs and Scandinavians 900 to 1300 AD. Leiden: Brill, 2007.
• _________. 'Kulturmötets konsekvenser. ”Slaviseringen” av den skandinaviska keramiktraditionen'. In: Arkeologi och mångkultur. Södertörn Archaeological Studies 4, red. Mats Burström, ss. 59-76. (2006): https://portal.research.lu.se/portal/en/publications/kulturmoetets-konsekvenser-slaviseringen-av-den-skandinaviska-keramiktraditionen(a9d3a126-7a32-4317-a3b3-f62612f50796).html