Pseudo-joint

local p1 = Workspace.Part1
local p2 = Workspace.Part2

function WeldAnchoredParts(part1, part2)
    coroutine.wrap(function()
        local s = Game:GetService("RunService")
        local originalspace = part2.CFrame:toObjectSpace(part1.CFrame)
        s.RenderStepped:connect(function()
            part1.CFrame = part2.CFrame:toWorldSpace(originalspace);
        end)
    end)()
end

WeldAnchoredParts(p1,p2)