Here is the trade that happened between the Nuggets and Wizards.
Sources: Washington has acquired Will Barton and Monte Morris from Denver for Kentavious Caldwell-Pope and Ish Smith
So the Nuggets are trying something new. I bet it's because of what happened last season and these two guys did help the Joker but not in a stretch that is expected from them unlike when Murray was around. But the stats from KCP and Ish was almost identical, and I would still pick the former players for chemistry strength.
Just weird though that they have to try something new this season when Jamal is going back to play. Both Barton is a good contributing to them, and trading him for KCP and Ish Smith doesn't have anything for the Nuggets to be honest. Maybe KCP wll become their corner 3' shooter when Jokic do a dribble penetrate and pass outside. But as you have said, there will be a chemistry issue with this new Denver players.
I think it is just fine that they try something new at this point. Their stars are not getting any younger and they have not reach the finals in this current team. Maybe this change can be good to them.
Chemistry will not be a problem long term. There can be issues in the first few months but it is not something that cannot be ironed out in a few months. In worst case scenario, they still have 82 games to play in NBA to get that chemistry going before they enter playoffs. It could be a rough start if that chemistry will really be a problem but it is fine as long as they get into playoffs. By that time, they have played enough games together to have a good chemistry and win when it matters the most, the playoffs and the finals.