I’m writing a script for a Swedish medieval movie, which is based in 15th century Sweden.
Tl; dr: Unless your villages located in the extreme frontier zone like Lapland, their parish life would largely follow as prescribed in medieval canon law books as elsewhere in Latin West, including the Mass.
Late 15th century Swedish local church apparently succeeded in re-building their authority as a local center of piety after the middle-14th century crisis (mainly) caused by the Black Death. Painters like Albertus Pictor (whose work, Death playing Chess is featured in Bergman's The Seventh Seal (Det sjunde inseglet)) were commissioned to decorate many local churches, and their wealth was strengthened by the increasing number of donations from lay people. Liturgical books from a few bishopric of medieval Sweden was also printed and circulated. Guilds with religious characteristics and/or confraternities also got popular as elsewhere in Late Medieval Europe, but a few of such communities' patrons were certainly specific to the Scandinavians, such as St. Cnut of Denmark and St. Olaf of Norway (Nilsson in Berntson, Nilsson & Wejryd 2012: 78-83).
Anyway, I suppose you at least live in Sweden or have one or more Swedish friends who can help you with their linguistic competence in Swedish. It would be a bit difficult to find almost any relevant literature in English, at least online. [Beskow 1999] (see the reference below) summarizes the daily life in the local parish from the morning to the night, so it would be easy to make use of for the fiction like your movie's script if you or your friend can read Swedish.
The following list of previous posts of mine might be of interest to you, but don't expect too much.
Recommended Literature:
(Edited): fixes typo.
As for online resource of the church life in medieval Sweden, you can also check the following site (in Swedish, sorry): https://stockholmslansmuseum.se/utstallningar/medeltida-kyrkor/
I find some jargons in medieval church architectures really awful in google translation, though.....
If you can "borrow" this collection of essays to check (Sven) Helander's article in English, you will be able to read something useful on medieval liturgy practiced in medieval Sweden by yourself (Helander is a specialist of medieval liturgy in Swedish dioceses) : https://archive.org/details/liturgyofmedieva0000unse/
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